Answer:
A gas is evolved
The ingredients can not be recovered
Explanation:
A chemical change is one in which a new substance is formed and it is not easily reversible.
One major ingredient used in cake baking is the baking powder or baking soda.
Baking a cake can be viewed as a chemical change. This is because, when the baking powder or soda is added in the presence of yeast, carbon dioxide gas is evolved as tiny bubbles of gas which makes the cake light and fluffy. Heat is equally given off in the process. The baking powder and other cake ingredients can not be recovered, hence, we can conclusively assert that a chemical change has taken place.
What information does a radioactive element's half-life tell you about that element?
Match the words to the correct descriptions.
Have different properties depending on the number of protons.
The ingredients maintain their properties when they are placed together or taken apart.
The atoms take on new properties when they bond together or are separated.
1.
Compounds
2.
Mixtures
3.
Atoms
Answer:
1. Atoms, Have different properties depending on the number of protons.
2. Mixtures, The ingredients maintain their properties when they are placed together or taken apart.
3. Compounds, The atoms take on new properties when they bond together or are separated.
Explanation:
Can anyone help me? :D
A student noticed a yellow, solid substance was formed when mixing two clear liquids during a lab. What term describes this yellow, solid substance?
A. physical change
B. exothermic reaction
C. endothermic reaction
D. precipitate
Answer:
D
Explanation:
a precipitate is formed from a solution
An neutral atom of aluminum 27 contains
Answer:Find it
Explanation:
Aluminium-27 is an isotope of aluminium characterized by the fact that is has a mass number equal to
27
.
Now, an atom's mass number tells you the total number of protons and of neutrons that atom has in its nucleus. Since you're dealing with an isotope of aluminium, it follows that this atom must have the exact same number of protons in its nucleus.
The number of protons an atom has in its nucleus is given by the atomic number. A quick looks in the periodic table will show that aluminium has an atomic number equal to
13
.
This means that any atom that is an isotope of aluminium will have
13
protons in its nucleus.
Since you're dealing with a neutral atom, the number of electrons that surround the nucleus must be equal to the number of protons found in the nucleus.
Therefore, the aluminium-27 isotope will have
13
electrons surrounding its nucleus.
Finally, use the known mass number to determine how many neutrons you have
This is a very long thing, Answer any of the questions that you can please anything helps just make sure you put the numbers for the questions you answer:
Question 1: Laws of Conservation of Matter and Energy (2 points)
a. Law of conservation of matter (1 point)
i. What does the law say about matter?
ii. What about matter can change and what does not change, according to the law?
b. Law of conservation of energy (1 point)
i. What does the law say about energy?
ii. What about energy can change and what does not change, according to the law?
Question 2: Phases of Matter (2 points)
a. What are the four states, or phases, of matter? Describe the shape and volume properties of each phase. Can they change, or are they fixed? (1 point)
i. _______________________
Shape:
Volume:
ii. _______________________
Shape:
Volume:
iii. _______________________
Shape:
Volume:
iv. _______________________
Shape:
Volume:
b. When heat energy is absorbed by matter, the matter's temperature increases. When heat energy is released by matter, the matter's temperature decreases. The matter can also change from one phase to another when heat energy is absorbed or released. Identify whether matter absorbs heat or releases heat as each of the following phase changes occur. (1 point)
i. From solid to liquid (melting)
ii. From liquid to solid (freezing or hardening)
iii. From liquid to gas (evaporation)
iv. From gas to liquid (condensation)
Question 3: Types of Energy (4 points)
a. List four kinds of energy. Give a brief definition of each. (1 point)
i. ______________________________________________________________
ii. ______________________________________________________________
iii. ______________________________________________________________
iv. ______________________________________________________________
b. Energy can change from one form to another. Describe the energy conversions in the following scenes. (1 point)
i. A kid falling out of a tree
ii. A scout rubbing sticks together to start a fire
iii. A man running a kerosene heater
c. What is the equation for calculating gravitational potential energy on the Earth? (1 point)
d. What is the equation for calculating kinetic energy (1 point)
Matter cannot be created or destroyed.
Further explanationConservation of mass applies to a closed system, where the masses before and after the reaction are the same
Or
Conservation of mass means:
In a closed/isolated system, the total mass of the substance before the reaction will be equal to the total mass of the reaction product.
So what changes is the form, into a liquid, gas or solid
while what does not change is the mass
What is the density at 27 °C of 28.0 milliliters of a liquid that has a mass of 4.05 grams?
Answer:
4.05/28=0.144g/ml
Explanation:
Which statement describes the relative energy of the electrons in the shells of a calcium atom?
Answer:
An electron in the first shell has more energy than an electron in the second shell.
Explanation:
someone help me please, I will give you brainliest
Answer:
conserve mass.
Explanation:
(WILL GIVE BRAINLIEST TO BEST ANSWER) What might a weak acid do to a rock?
When water combines with carbon dioxide in the atmosphere, it will form carbonic acid, which is a weak acid. If this weak acid comes in contact with a rock, it will cause some of the rock to be dissolved. This process can also be referred to as weathering.
1. Alpha emission by a radium-226 nucleus
Answer:
₈₈Ra²²⁶ → ₈₆Rn²²² + ₂He⁴ + energy
Explanation:
Alpha beta and gamma radiations are the examples of ionizing radiations.
Alpha radiations are emitted as a result of radioactive decay. The atom emit the alpha particles having two proton and two neutrons. It is also called helium nuclei. When atom undergoes the alpha emission the original atom convert into the atom having mass number less than 4 and atomic number less than 2 as compared to parent atom.
For example:
₈₈Ra²²⁶ → ₈₆Rn²²² + ₂He⁴ + energy
Properties of alpha radiation:
Alpha radiations can travel in a short distance.
These radiations can not penetrate into the skin or clothes.
These radiations can be harmful for the human if these are inhaled.
These radiations can be stopped by a piece of paper.
Another example:
₉₂U²³⁸ → ₉₀Th²³⁴ + ₂He⁴ + energy
It is determined that a metal sample contains 0.251 moles of iron. How many iron atoms are in the sample?
Given parameters:
Number of moles of iron = 0.251 moles
Unknown:
Number of atoms = ?
Solution:
A mole of an atom contains the Avogadro's number of particles;
Avogadro's particles = 6.02 x 10²³ atoms
1 mole of atom = 6.02 x 10²³ atoms
0.251 moles = 0.251 x 6.02 x 10²³ = 1.51 x 10²³ atoms
The number of atoms here is 1.51 x 10²³ atoms
The number of atoms in 0.251 mol of Iron sample has been [tex]1.51\;\times\;10^2^3[/tex].
The number of atoms in a mole of sample has been given by the Avogadro law. According to the Avogadro law, the number of atoms in 1 mole of sample has been equivalent to the Avogadro number.
The Avogadro number has been a constant quantity with the value of [tex]6.023\;\times\;10^2^3[/tex].
Computation for Iron atomsThe given mole of iron has been 0.251 mol.
The number of atoms in the sample has been given as:
[tex]\rm 1\;mol=6.023\;\times\;10^2^3\;atoms\\ 0.251\;mol=0.251\;\times\;6.023\;\times\;10^2^3\;atoms\\ 0.251\;mol=1.51\;\times\;10^2^3\;atoms[/tex]
The number of atoms in 0.251 mol of Iron sample has been [tex]1.51\;\times\;10^2^3[/tex].
Learn more about number of atoms, here:
https://brainly.com/question/1152162
which group has different numbers of valence electrons
Answer:
where are the group?
Explanation:
Answer:
Transition metals
Explanation:
At point R, rocks melt underground to form magma. Which is another process that contributes to the formation of rock at point R?
compacting of sediments on the mountain
cooling as the lava runs down the mountain
weathering of the mountain from the environment
eroding of different rocks at the base of the mountain
Another process that contributes to the formation of rock at point R is the:
B. Cooling as the lava runs down the mountainAccording to the given question, we need to find another process which can help with the rock formation at point R where the rock melts underground to form magma.
As a result of this, another process through which makes a significant contribution to the formation of rock at point R is the cooling of the lava as the magma which has been melted runs down the mountain.
Therefore, the correct answer is option B
Read more here:
https://brainly.com/question/14886424
Mercury, the only metal that is liquid at room temperature, has a density of 13.6g/cm^3. How much does 25cm^3 of mercury weigh?
Answer:
The mercury with volume of 25 cm³ having weight of 340 g.
Explanation:
Given data:
Density of mercury = 13.6 g/cm³
Volume of mercury = 25 cm³
Mass of mercury = ?
Solution:
We will apply density formula.
d = m/v
13.6 g/cm³ = m/ 25 cm³
m = 13.6 g/cm³ × 25 cm³
m = 340 g
The mercury with volume of 25 cm³ having weight of 340 g.
Determine the mass of 3.45 moles of Cobalt.
Answer:
203g
Explanation:
Multiply #moles by cobalt's molar mass:
molar mass= 58.9332g/ 1 mole)
3.45 mole Cobalt (58.9332g/ 1 mole)= 203g <-- 3 significant figures
According to the mole concept, mass of 3.45 moles of cobalt is 203.30 g.
What is a mole?Mole is defined as the unit of amount of substance . It is the quantity measure of amount of substance of how many elementary particles are present in a given substance.
It is defined as exactly 6.022×10²³ elementary entities. The elementary entity can be a molecule, atom ion depending on the type of substance. Amount of elementary entities in a mole is called as Avogadro's number.
It is widely used in chemistry as a suitable way for expressing amounts of reactants and products.For the practical purposes, mass of one mole of compound in grams is approximately equal to mass of one molecule of compound measured in Daltons. Molar mass has units of gram per mole . In case of molecules, where molar mass in grams present in one mole of atoms is its atomic mass.
Mass of 3.45 moles of cobalt is obtained as, mass=number of moles ×molar mass
Substitution of values gives ,mass=3.45×58.93=203.30 g.
Thus, the mass of 3.45 moles of cobalt is 203.30 g.
Learn more about moles,here:
https://brainly.com/question/20486415
#SPJ2
what is the differences of sitsiritsit and atin cu pung singsing
Answer:
'Sitsiritsit' is a popular folk song of Filipino.
'Atin cu pung singsing' is a popular folk song of Kapampangan.
Explanation:
'Sitsiritsit' is a popular folk song of Filipino.
The song presents a picture of the rustic life that the people used to live. It focuses on the life of the people during the Spanish colonization.
In the song, a woman yells and threatens at a store owner. She asks him to increase the limit of the credit amount or the ants will get him.
'Atin cu pung singsing' is a popular folk song of Kapampangan.
The song presents the feelings of a girl who is looking for her lost ring. She feels very gloomy about this. She brings a proposal that whoever would bring her the ring would be her love forever.
F. A rigid steel cylinder has a volume of 20.0 L. It is filled with N2 gas to a final pressure of 205 atm at 27.0 S. How
many moles of N2 gas does the cylinder contain?
Answer:
don't know this but going to figure out
What's another word for hypothesis
Answer:
Explanation:
theory
theorem
thesis
conjecture
supposition
speculation
postulation
postulate
proposition
premise
surmise
assumption
presumption
prediction
How many molecules are in 2,10 mol CO2?
0 3.79 X 1024 molecules
O 2.53 x 1024 molecules
O 1.26 X 1024 molecules
O 3.49 * 10-24 molecules
Answer:
the answer is the 3rd option
Explanation:
which is 1.26 x 1024 calculating with avogardos law
Answer:
1.26 X 1024 molecules
Explanation:
*ANSWER FAST AND YOU WILL GET BRAINLIEST* -
According to le châteliers principle how would a change in pressure affect a gaseous system in equilibrium?
A. All equilibrium interactions would stop
B. The equilibrium would shift in the direction of the change
C. The number of both reactants and products would increase
D. The equilibrium would shift to reduce the pressure change
Answer:
D.
Explanation:
Answer:
The correct answer is d. i took the test and got it right
Explanation:
(PLEASEE HELPPP) A topographic map of part of Arizona is shown below which of the labeled points on the map has the steepest slope?
A) 1
B) 3
C) 2
D) 4
Answer:
I think A is the answer Hope I'm right
How do the lines of the brain and the neurons work together to communicate
***BRAINLIEST ASNWERRR***
How many grams are in 34.2 moles of Lithium (Li)?
Mass of Li = 237.38 g
Further explanationThe mole itself is the number of particles contained in a substance amounting to 6.02.10²³
[tex]\large {\boxed {\boxed {\bold {mol = \frac {mass} {molar \: mass}}}}[/tex]
KnownMoles of Li = 34.2
Molar mass(MW) of Li = 6.941 g/mol
then mass of Lithium (Li) :
[tex]\tt mol=\dfrac{mass}{MW}\\\\mass=mol\times MW\\\\mass=34.2\times 6,941~g/mol\\\\mass=\boxed{\bold{237.38~g}}[/tex]
Help me ASAP !!!!!!!!!!!!!!!
Answer:
l, ll, lll, v
Explanation:
I just took the test ;)
HURRY ⚠️
How many Chlorine atoms in 2HCI?
Hiw many Hydrogen atoms are in 2HCl?
Answer:
2 in each
Explanation:
Which is the electron configuration for zinc?
Answer:
1s22s22p63s23p64s23d10
Explanation:
This is the answer to the electron configuration for zinc.
When Juan got home from school, he noticed a foul smell coming from the kitchen. He decided to investigate the smell and found fruit sitting on the counter. There was evidence that a chemical reaction had occurred. When he looked at the fruit, he saw that it had turned brown and was soft to the touch. Write a short claim evedence and reasoning. If you could separate them it would be geat
Answer:
See explanation
Explanation:
A chemical reaction is said to have occurred when there is a permanent, irreversible change in a substance.
Considering the fruit in the question, the changes in the fruit can not be reversed. Nothing can ever be done to return the fruit to its original form. This ultimately shows that a chemical reaction has taken place.
Secondly, the occurrence of a chemical reaction can be confirmed by evolution of a gas. The foul smell that filled the kitchen is the gas evolved during the chemical reaction involving the rotten fruit.
A sample of pure lithium nitrate contains 10.1% lithium by mass. What is the % lithium by mass in a sample of pure lithium carbonate that has twice the mass of the frost sample?
The % lithium by mass in a sample of pure lithium carbonate : 18.79%
Further explanationProust states the Comparative Law that compounds are formed from elements with the same Mass Comparison so that compounds have a fixed composition of elements
% Lithium (Li) in Li₂CO₃(lithium carbonate) will remain the same even if the mass amount of Li₂CO₃ changes
Ar of Li = 6.941 g/mol
MW of Li₂CO₃ = 73.891 g/mol
[tex]\tt \%Li=\dfrac{2.Ar~Li}{MW~Li_2CO_3}\times 100\%\\\\\5Li=\dfrac{2\times 6.941}{73.891} \times 100\%=18.79\%[/tex]
One difference between mixtures and pure substances is that
A)
mixtures can be physically separated.
B)
mixtures are made of one type of atom.
pure substances have no chemical bonds
D)
pure substances can be physically separated,
ning
Answer:
I think b but I could be wrong
Answer:
a
Explanation:
i just took it
