Please help me thank you, I will mark you?!?!?.:;)))

Please Help Me Thank You, I Will Mark You?!?!?.:;)))

Answers

Answer 1

Answer:

a change from a solid to a liquid

Explanation:

Answer 2

Answer:

Dissolving salt in water is a chemical change.

Explanation:

A log burning is a chemical reaction, but not change. All the others are obviously not the answer.


Related Questions

wich of these does the sun provide in large amounts 1.carbon dioxide 2.energy 3.glucose 4.oxygen​

Answers

Answer:

2. Energy

Explanation:

Explain the Rules that determine how electrons are arranged around the nuclei of atoms. Use examples to explain the rules/principles.

Answers

Can i get brainliest :)

Viewed simply, electrons are arranged in shells around an atom's nucleus. Electrons closest to the nucleus will have the lowest energy. Electrons further away from the nucleus will have higher energy. ... In a more realistic model, electrons move in atomic orbitals, or subshells.

By definition:

there are 7 energy levelsthere are 4 sub-levelsAufbau's principle is a principle of atomic physics, which explains how electrons are accommodated in their orbits.Example: for hydrogen, its electronic configuration would be: 1s¹.

The Electronic Configuration of the elements is the arrangement of all electrons of an element in energy levels and sub-levels (orbitals).  

There are 7 energy levels, numbered from 1 to 7, and in which electrons are distributed, logically in order according to their energy level. Electrons with less energy will be spinning at level 1.

Each level is divided into sub-levels. These sub-levels into which each level is divided can be up to 4. These 4 sub-levels are called: s, p, d, f.

In the sub-level s there can only be a maximum of 2 electrons, in sub-level p there can be a maximum of 6 electrons, in the sub-level d 10 electrons and finally in the sub-level f there can be a maximum of 14 electrons.

Aufbau's principle is a principle of atomic physics, which explains how electrons are accommodated in their orbits around the nucleus of the atom. This principle states that the filling of these orbitals occurs in increasing order of energy, that is, from the orbitals of lower energy to those of higher energy.

The simplest of the sub-levels is 1s. If you fill the 1s you can start filling the 2s. After the 2s sub-level is satisfied, the 2p can begin to fill and so on. The order is:  

1s²2s²2p⁶3s²3p⁶4s²3d¹⁰4p⁶5s²4d¹⁰5p⁶6s²4f¹⁴5d¹⁰6p⁶7s²5f¹⁴6d¹⁰7p⁶

In this way, taking into account the atomic number Z of the element (which represents the number of protons of the element, and in a neutral atom it also indicates the number of electrons), the electrons that it has in the orbitals will be placed following the previously established.

For example, for hydrogen, whose atomic number is Z = 1, its electronic configuration would be: 1s¹.

Remember that the number 1 that precedes the representative letter of the orbital indicates the level of energy where the electron is located, the letter s indicates the type of orbital where the electron is located, and the exponent 1 indicates the number of electrons that are located in said orbital.

In summary:

there are 7 energy levelsthere are 4 sub-levelsAufbau's principle is a principle of atomic physics, which explains how electrons are accommodated in their orbits.Example: for hydrogen, its electronic configuration would be: 1s¹.

Learn more:

https://brainly.com/question/5429660

Questions 4-6: Use the following Molar Masses:
H2: 2.02 g/mol Oz: 32.00 g/mol H2O: 18.02 g/mol
5) What mass of oxygen is needed to completely react
with 32.0 g of hydrogen?
2 Hz O2 → 2 H2O
+
32 g H2
х
x
x
= 329 H2
= 1g 42
= 2.02 g H2
= 1 mol H2
* 2.02 mol H2
- 2 mol H2
# 1 mol O2
- 2 mol O2
# 32 mol Oz
3 32 mol O2
=> 32 g 02
- 1 g 02
= 1013 g 02
: 0.248 g 02
253.4 g 02

Answers

Answer:

Mass =   253.4 g

Explanation:

Given data:

Mass of oxygen required = ?

Mass of hydrogen available = 32.0 g

Solution:

Chemical equation:

2H₂ + O₂     →       2H₂O

Number of moles of hydrogen:

Number of moles = mass/molar mass

Number of moles = 32.0 g/ 2.02 g/mol

Number of moles = 15.84 mol

Now we will compare the moles of hydrogen and oxygen:

                  H₂         :           O₂

                   2          :           1

              15.84        :         1/2×15.8 = 7.92 mol

Mass of oxygen required:

Mass = number of moles × molar mass

Mass = 7.92 mol × 32.00 g/mol

Mass =   253.4 g

how to be happy, i miss them

Answers

you have to not let your past or your sad thoughts get the best of you.. that what I do i do get sad sometimes but dont let that get u down

Answer:

focus on whats ahead of u, not behind u ok?

Explanation:

hope this helps

Which molecule has a dipole moment?
A. Cl2 (linear geometry)
B. H2S (bent geometry)
C. CCIA (tetrahedral geometry)
D. CO2 (linear geometry)

Answers

B. I think im probly wrong

Many tests to distinguish aldehydes and ketones involve the addition of an oxidant. Only __________ can be easily oxidized because there is_________ next to the carbonyl and oxidation does not require _______

Answers

Answer:

AldehydesA hydrogen atomOxygen

Explanation:

Many tests to distinguish aldehydes and ketones involve the addition of an oxidant. Only aldehydes can be easily oxidized because there is a hydrogen atom next to the carbonyl and oxidation does not require oxygen

Li2SO4 _____ an electrolyte in solution.
A. Is
B. Is not

Answers

Answer:

a

Explanation:

it is an electrolyte because of its strong polar chemical bond

It is an electrolyte because it is ionic!

What ratio of nitrogen and hydrogen molecules would result in no left-over reactants? Explain your answer.

Answers

Answer:

1:3

Explanation:

nitrogen and hydrogen combine qt high pressure and temperature to form ammonia gas.this method is used to prepare ammonia industrially and the process is called haber's process.

the balanced equation is given as:

N2+3H2=>2NH3

we can see that 1 mole of nitrogen combines with 3 moles of hydrogen to produce 2 moles of ammonia.

hence ratio of nitrogen and hydrogen molecules should be 1:3 for reactants to get used up completely.

I hope it's helpful!

2. How do the ancient Greek model and Ptolemy's model differ?

Answers

Answer:

Greek's Model used stars while Ptolemy did not use stars.

Explanation:

The Greek model had stars as part of the system and they revolved around the Earth. Ptolemy's model did not include the stars, but it did include the moons that revolves around the planets.

6. How many ions of Na are in 45.6 g of Na2SO4?

Answers

Answer:

3.85 ×10²³ Na⁺ ions

Explanation:

Given data:

Mass of Na₂SO₄ = 45.6 g

Number of ions of Na = ?

Solution:

Number of moles of Na₂SO₄:

Number of moles = mass/ molar mass

Number of moles = 45.6 g/ 142.04 g/mol

Number of moles = 0.32 mol

1 mole of Na₂SO₄ contain 2 moles of Na⁺ ion.

0.32 mol × 2=  0.64  moles of Na⁺ ion

1 mole contain 6.022×10²³ Na⁺ ions

0.64 mol × 6.022×10²³ Na⁺ ions / 1 mol

3.85 ×10²³ Na⁺ ions

Which of these is a harmful interaction

Answers

Answer:The five major types of species interactions, summarized in Figure 10, are competition, predation, parasitism, mutualism, and commensalism.

Explanation:

2055 Q. No. 10^-2
mole of KOH is dissolved in 10 litres of
water. What will be the pH of the solution?
12
Ans: pH = 11​

Answers

Answer:

11

Explanation:

Moles of KOH = [tex]10^{-2}[/tex]

Volume of water = 10 liters

Concentration of KOH is given by

[tex][KOH]=\dfrac{10^{-2}}{10}\\\Rightarrow [KOH]=10^{-3}\ \text{M}[/tex]

[tex][KOH][/tex] is strong base so we have the following relation

[tex][KOH]=[OH^{-}]=10^{-3}\ \text{M}[/tex]

[tex]pOH=-\log [OH^{-}]=-\log10^{-3}[/tex]

[tex]\Rightarrow pH=14-3=11[/tex]

So, pH of the solution is 11

QUESTION 20
A slice of pizza contains 17 g of fat, 25 g of carbohydrate, and an unknown amount of protein. If the piece of pizza contains a total of 750 kcal,
how many grams of protein does the slice of pizza contain? (The accepted caloric values for foods are 4.0 kcal/g for carbohydrate, 9.0 kcalg
for fat, and 4.0 kcal/g for protein.) Report the answer to 2 significant figures.
429
O Can not be determined from the given information.
O 649
O 749
120 g
Save All Answ
MacBook Pro

Answers

Answer:

Explanation:

Let the protein contained in pizza be m gram .

calories contained by 17 g of fat = 17 x 9  kcals = 153  kcals .

calories contained by 25 g of carbohydrate = 25 x 4  kcals = 100 kcals .

calories contained by m  g of protein  = m  x 4  kcals = 4 m  kcals .

Total calories of slice of pizza = 153 + 100 + 4m kcals

= 253 + 4m kcals

Given ,

253 + 4m = 750

4m = 497

m = 124.25 g .

120 g ( rounded to two significant  figures )

During the process of condensation, water vapor:____________.
(1) releases 334 J/g of heat energy
(2) releases 2260 J/g of heat energy
(3) gains 334 J/g of heat energy
(4) gains 2260 J/g of heat energy

Answers

Answer: (2) releases 2260 J/g of heat energy

Explanation:

Latent heat of vaporization is the amount of heat required to convert 1 mole of liquid to gas at atmospheric pressure.

Latent heat of condensation is energy released when 1 mole of  vapor condenses to form liquid droplets.

The temperature does not change during this process, so heat released goes into changing the state of the substance, thus it is called latent which means hidden. The energy released in this process is same in magnitude as latent heat of vaporization. The heat of condensation of water vapour is about 2,260 J/g.

Phase transition refers to the changes in the states of matter between gas, liquids, and solids.

The correct answer is:

Option 2. releases 2260 J/g of heat energy

The process can be explained as:

1. Condensation is the process of conversion of water vapor into the liquid state.

2. Latent heat of vaporization is defined as the amount of heat required for 1 mole of liquid to convert into a gaseous phase at atmospheric pressure.

3. The change in the temperature does not occur during the condensation, and the heat required for the phase transition is latent heat. The heat of condensation of water vapor is 2,260 J/g.

Thus, the correct answer is Option 2.

To know more about condensation, refer to the following link:

https://brainly.com/question/15563071

A similarity ratio of scale factor is the ratio of the lengths of the corresponding of two similar polygons

Answers

Answer:

go to hellfhshahahahahahahahahaha  aha

Explahhhhahah

The most common source of copper (CuCu) is the mineral chalcopyrite (CuFeS2CuFeS2). How many kilograms of chalcopyrite must be mined to obtain 395 gg of pure CuCu

Answers

Answer:

1.14kg of chalcopyrite

Explanation:

In 1 mole of chalcopyrite, CuFeS₂, there is 1 mole of Cu. Thus, to solve this question we need to convert the mass of pure Cu to moles using molar mass (Cu = 63.546g/mol). Then, the moles of Cu are equal to moles of chalcopyrite that must be converted to grams and then to kg (CuFeS₂: 183.54g/mol)

Moles Cu:

395g Cu * (1mol / 63.546g) = 6.216 moles Cu = 6.216 moles CuFeS₂

Mass chalcopyirite:

6.216 moles CuFeS₂ * (183.54g/mol) = 1140.9g

In kilograms:

1140.9g * (1kg / 1000g) =

1.14kg of chalcopyrite

Scientists did not know about cells before the 1600s because the
microscope had not been invented yet. *
O True
False

Answers

True, cells were first discovered in 1665 by Robert Hooke.

What is the name of the following compound? Se5S6

Answers

Answer:

I'm sorry I couldn't find it, I looked all over the internet

Suppose you have 2.50 L of a substance with a density of 8.00 g/mL and you want to determine the mass of the substance. The calculation can be broken down into three steps. First, convert the volume from liters to milliliters. Then, determine the mass of the sample in grams. Finally, convert the mass from grams to kilograms. Show the unit analysis by placing the correct components into the unit‑factor slots. The question marks (?) represent the answer to the previous step.

Answers

Answer:

20 kg

Explanation:

From the question given above, the following data were obtained:

Volume (V) of substance = 2.50 L

Density (D) of substance = 8.00 g/mL

Mass (m) of substance =?

Next, we shall convert 2.50 L to millilitres (mL). This can be obtained as follow:

1 L = 1000 mL

Therefore,

2.50 L = 2.50 L × 1000 mL / 1 L

2.50 L = 2500 mL

Thus, 2.50 L is equivalent to 2500 mL.

Next, we shall determine the mass of the substance. This can be obtained as follow:

Volume (V) of substance = 2500 mL

Density (D) of substance = 8.00 g/mL

Mass (m) of substance =?

D = m / V

8 = m / 2500

Cross multiply

m = 8 × 2500

m = 20000 g

The mass of the substance is 20000 g.

Finally, we shall convert 20000 g to Kg

This can be obtained as follow:

1000 g = 1 kg

Therefore,

20000 g = 20000 g × 1 kg / 1000 g

20000 g = 20 kg

Therefore, the mass of the substance is 20 Kg


How many atoms are there in 4430 grams of lithium (Li)?

Answers

Answer:

3843.96 × 10²³ atoms

Explanation:

Given data:

Mass of Li = 4430 g

Number of atoms = ?

Solution:

We will calculate the number of moles first.

Number of moles =mass/molar mass

Number of moles = 4430 g/ 6.94 g/mol

Number of moles = 638.32 mol

1 mole contain 6.022 × 10²³ atoms

638.32 mol × 6.022 × 10²³ atoms / 1 mol

3843.96 × 10²³ atoms

A photon of light has an energy of 1.83 x 10-18). What is the wavelength of this light? Does this light fall in the IR, visible, or UV region of the electromagnetic spectrum?​

Answers

Answer:

1.09 × 10⁻⁷ m

UV region

Explanation:

Step 1: Given and required data

Energy of the photon of light (E): 1.83 × 10⁻¹⁸ J

Planck's constant (h): 6.63 × 10⁻³⁴ J.s

Speed of light (c): 3.00 × 10⁸ m/s

Step 2: Calculate the wavelength (λ) of this photon of light

We will use the Planck-Einstein's relation.

E = h × c/λ

λ = h × c/E

λ = 6.63 × 10⁻³⁴ J.s × (3.00 × 10⁸ m/s)/1.83 × 10⁻¹⁸ J = 1.09 × 10⁻⁷ m

This wavelenght falls in the UV region of the electromagnetic spectrum.

Calculate the mass of sodium bicarbonate produced bu complete decompostion of 16.8h of nahco3

Answers

Answer:what is nacho3???

Explanation:

Following intense exercise, the blood pH was determined to be 7.1. If the HCO3- is 7.5mM and the pKa for HCO3- is 6.1, what is the CO2 concentration in the blood

Answers

Answer:

[tex]0.75\ \text{mM}[/tex]

Explanation:

Concentration of [tex]HCO_3^-[/tex] = [tex][HCO_3^-]=7.5\ \text{mM}[/tex]

[tex]pK_a[/tex] for [tex]HCO_3^-[/tex] = 6.1

[tex]pH[/tex] of  blood = 7.1

The reaction is as follows

[tex]H_2CO_3+H_2O\rightarrow HCO_3^-+H_3O^+[/tex]

From the Henderson equation we get

[tex]pH=pK_a+\log\dfrac{[HCO_3^-]}{[H_2CO_3]}\\\Rightarrow 7.1=6.1+\log \dfrac{7.5}{[H_2CO_3]}\\\Rightarrow 1=\log\dfrac{7.5}{[H_2CO_3]}\\\Rightarrow 10^1=\dfrac{7.5}{[H_2CO_3]}\\\Rightarrow [H_2CO_3]=\dfrac{7.5}{10}\\\Rightarrow [H_2CO_3]=0.75\ \text{mM}[/tex]

[tex]CO_2(g)+H_2O(l)\rightarrow H_2CO_3(aq)[/tex]

Concentration of [tex]H_2CO_3[/tex], [tex][H_2CO_3]=[CO_2][/tex]

Concentration of [tex]CO_2[/tex], [tex][CO_2]=[H_2CO_3]=0.75\ \text{mM}[/tex].

This is something I really need help in pls

Answers

it’s 2.5 m/s i believe

Answer:

3 m/s2

Explanation:

i looked it up on quizizz and it showed 3 m/s2

This is not multiptle choice
Sound: Now click the Sound tab.

Part A
On the Sound tab, investigate briefly all the phenomena you explored with water waves above and describe any similarities in your results for sound. Specifically, describe

wave pattern as seen on the screen
shape and amplitude of the graph
effect of frequency on wavelength
effect of frequency on velocity
pattern with two sources
wave pattern with a single-slit barrier

Question 3
Light: Now click the Light tab.

Part A
On the Light tab, once again investigate briefly all the phenomena you explored with water and sound above. Describe any similarities in your results for light. Specifically describe

wave pattern as seen on the screen
shape and amplitude of the graph
effect of frequency on wavelength
effect of frequency on velocity
pattern with two sources
wave pattern with a single-slit barrier

Answers

Answer: Sound waves

The wave pattern that i observed in sound waves are longitudinal wave patterns.

The mathematical graph function looks like is a sine function graph. The pattern that i observed in the amplitude of the wave is longitudinal wave pattern

When you increase the frequency of the sound waves the wave moves faster but the wavelength becomes shorter. The higher the frequency results in higher the pitch of the sound.

If you increase the frequency the velocity of the sound wave remains constant for all valuses of frequencies.

i am currently completing this assigment. i am not usre if the answer are correct but i tried my best  

I also got this from course hero it's your choise to put the one you want.

The wave pattern is identical to the pattern of the water. The graph is the same as the water except the wave height isn’t as big. Increasing the frequency increases the wavelength. Increasing the frequency also increases the velocity of the waves by a lot. With two sources the waves pass through each other. The wave pattern with a single slit barrier is the same as the water pattern.

Explanation:

Answer: Sound waves

The wave pattern that i observed in sound waves are longitudinal wave patterns.

The mathematical graph function looks like is a sine function graph. The pattern that i observed in the amplitude of the wave is longitudinal wave pattern

When you increase the frequency of the sound waves the wave moves faster but the wavelength becomes shorter. The higher the frequency results in higher the pitch of the sound.

If you increase the frequency the velocity of the sound wave remains constant for all valuses of frequencies.

i am currently completing this assigment. i am not usre if the answer are correct but i tried my best  

I also got this from course hero it's your choise to put the one you want.

The wave pattern is identical to the pattern of the water. The graph is the same as the water except the wave height isn’t as big. Increasing the frequency increases the wavelength. Increasing the frequency also increases the velocity of the waves by a lot. With two sources the waves pass through each other. The wave pattern with a single slit barrier is the same as the water pattern.

Explanation:

The density of aluminum is 2.7 g/mL if I add a piece of aluminum to a graduated cylinder of water in the water level increases by 8.2 ML what is the mass of the piece of aluminum

3.0 g
22 g
5.5 g
0.33 g

Answers

The answer would be 5.5g because you have to subtract 8.2 minus 2.7 and you get 5.5g so basically the answer is C.

1. How many moles of sulfur are in 40g of sulfur?

Answers

Answer:

1 sulfur

Explanation:

1 mole is equal to 1 moles Sulfur, or 32.065 grams

Answer:

[tex]\boxed {\boxed {\sf 1.24727159 \ moles \ of \ sulfur }}[/tex]

Explanation:

To convert from grams to moles, we must use the molar mass found on the Periodic Table of Elements.

1. Molar Mass

This is a sample of sulfur, so look for S on the table.

S: 32.07 g/mol

2. Convert from Grams to Moles

Use the molar mass as a ratio.

[tex]\frac { 32.07 \ g \ S}{ 1 \ mol \ S }[/tex]

Multiply by the given number of grams: 40

[tex]40 \ g \ S * \frac { 32.07 \ g \ S}{ 1 \ mol \ S }[/tex]

Flip the fraction so the grams of sulfur will cancel each other out.

[tex]40 \ g \ S * \frac {1 \ mol \ S }{ 32.07 \ g \ S}=40* \frac {1 \ mol \ S }{ 32.07 }[/tex]

[tex]\frac {40 \ mol \ S } { 32.07 } = 1.24727159 \ mol \ S[/tex]

There are 1.24727159 moles of sulfur.

The speed of a wave in the string is 16.2ms. The mass per unit length of the string is 0.3ms calculate tension in the string

Answers

Answer:

The tension in the string is 78.73 N.

Explanation:

The tension in the string can be determined from the expression;

v = [tex]\sqrt{\frac{T}{m} }[/tex]

where: v is the speed of the wave in the sting, T is the tension in the string and m is the mass per unit length of the sting.

Given that: v = 16.2 m/s, and m = 0.3 kg/m.

Then;

16.2 = [tex]\sqrt{\frac{T}{0.3} }[/tex]

Square both sides to have,

[tex](16.2)^{2}[/tex] = [tex]\frac{T}{0.3}[/tex]

T = [tex](16.2)^{2}[/tex] x 0.3

  = 252.44 x 0.3

  = 78.732

T = 78.732 N

The tension in the string is 78.73 N.

What is the velocity of a plane to travel 3000 miles from New York to California in 4.5 hours

Answers

Answer:

[tex]velocity = \frac{displacement}{time} \\ v = \frac{3000}{4.5} \\ v = 666.67 \: miles \: per \: hour \\ or \\ v = 666 \frac{2}{3} \: miles \: per \: hour[/tex]

Which of the processes is exothermic?
a) evaporation of alcohol
b) sublimation of iodine
c) solidification of volcanic lava
d) burning of paper​

Answers

Answer:

Choice C as my opinion

Explanation:

solidification of volcanic lava has to do with changes in earth and the thermal structure that's just a point not sure though

hope I was helpful though thank you

Answer:

c) solidification of volcanic lava

Explanation:

heat is being lost to the outside surroundings "exo" thermic

Other Questions
Worth 20 points, please help and give good answers than you(will mark brainlest) Ankit makes 74% of the free throws he takes in his basketball league. If he is fouled on a three-point shot and gets three free throws, what is the approximate probability he will make all three shots?40.5%74%54.8%99.8%22.2% Spanish answer all please What terms in the question need to be defined List and describe three common defense mechanisms. Description is needed. the leaders were discussing the effect of global warming ( change to passive voice) today is the worst day ever.my school has two options; you do work online or in person.im on my period today and it hurts a LOT. this is the first time it hurts this bad that I can't even stand up. not to mention i also feel like vomiting. i usually go to school in person. yes, ik about corona-virus. my mom doesn't care.i told her if today i can stay home and shes angry, shes complaining about my studies and how my cousins are better than me. honestly i cant put up with this. what do i do? 1. Who is our current chief of executive (president)? a)Hillary Clinton b)Joseph Biden c)Bernie Sanders d)Donald J. Trump Name three divisions of cryptograms? plz i will follow you What have you learned about the characteristics of a healthy school and community environment? just only 3 sentence, i will follow you... all of the genetic material in an organism. a.) genome b.) stem cell c.)GMO Please help!Solve for C: S = C + RC what is 0.35 as a simplified fraction and why?? Help plz!!!!!!!!!!!!!!!!!! strategies for preventing accidents Paano maaaring mapanatili ang pagkakasundo atmagandang samahan ng magkakapatid? Bakit mahalagangmaging maayos ang samahan ngmagkakapatid? Identify two checks on power in the Roman Republic. Do you think Hugh would have been able to perform this experiment in his laboratory at home 20 years ago? Explain your answer. PLZ HELP 34 pointsSelect the correct text in the passage.Read this excerpt from President Franklin Roosevelts speech following Japans attack on Pearl Harbor. Which two parts show the presidents confidence that the United States will win the war against Japan?The facts of yesterday and today speak for themselves. The people of the United States have already formed their opinions and well understand the implications to the very life and safety of our Nation.As Commander in Chief of the Army and Navy I have directed that all measures be taken for our defense.But always will our whole Nation remember the character of the onslaught against us.No matter how long it may take us to overcome this premeditated invasion, the American people in their righteous might will win through to absolute victory. I believe that I interpret the will of the Congress and of the people when I assert that we will not only defend ourselves to the uttermost but will make it very certain that this form of treachery shall never again endanger us.Hostilities exist. There is no blinking at the fact that our people, our territory, and our interests are in grave danger.With confidence in our armed forceswith the unbounding determination of our peoplewe will gain the inevitable triumph- so help us God PLEASE HELP ME WITH THIS I WILL GIVE BRAINLIEST