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Answer:

320 ml

Explanation:

Answer: energy

Explanation:hope this helps.

Answer:

Temperature

Explanation:

1. Q = 4085.25 J

2. Q = 6288.75 J

Heat can be calculated using the formula:  

Q = mc∆T  

A calorimeter is a device used to measure the specific heat of material  

1. mass of water : m= 75 g

T1 = 26°C

T2 = 39°C

Csp = 4.19 J/g°C.

[tex]\tt Q=m.c.\Delta T\\\\Q=75\times 4.19\times (39-26)\\\\Q=4085.25~J[/tex]

2.mass of iron = 215 g

T1 = 25°C

T2 = 90°C

Csp = 0.45 J/g°C.

[tex]\tt Q=m.c.\Delta T\\\\Q=215\times 0.45\times (90-25)\\\\Q=6288.75~J[/tex]

Answer:

magnesium

Explanation:

magnesium is in Group 2, in the periodic table. this means that it has 2 valence electrons. the less valence electrons an element or atom has, the more reactive. Selenium has 6 valence electrons. as a result, Mg is more reactive

Answer:

Each atom is left with a complete outer shell. An ionic bond forms between a metal ion with a positive charge and a nonmetal ion with a negative charge.

HOPE DAT HELPS BRO!

Answer:

the answer is isotopes

I hope this will help you

Answer:

and the last name then select a City the solution if they are getting elimination method if I can tell u that is telling you about me to this email and delete this email and any attachments may contain confidential information and rupees hundred years ago the pair in the solution if I can tell you my story of my teacher not respond please ask me to this email and any attachments is intended only for the independence of Bangladesh and what is the correct answer is yes we have to come at your earliest convenience and what is the correct answer

Answer:

If you are asking to suggest a method to preserve the extinction of this species of pigeon then

1. Governments should derive a law that will prevent hunting of these pigeons.

2. These pigeons should be given a place in sanctuaries with hospitable habitat made available.

3. If someone sees a bird of this kind care should be taken not to harm it intentionally or accidentally.

4. Breeding this type of Birds should be Promoted to increase their number

Answer:

yess

Explanation:

Answer:

D

Explanation:

A and C sounds not logic

B is wrong since all the molecules has different numbers of carbon and hydrogen

D sounds correct because triple covalent bond exist at the C-C bonding

Answer:

what do you need help with?

Explanation:

Answer:

D - He was the first person to use the term Cells.

Explanation:

Hooke invented the first compound light microscope (not first microscope) and he examined a cork and saw that it was made up of thousands of empty pockets which he later called 'Cells'.

Hope it Helps! :D

Answer:

c.

Explanation:

One of the main differences between an atom and an element is that an atom can be combined but an element cannot be combined. There are many combinations of atoms that make up different gases, liquids, and solids each with a unique makup. For example, water is made up of two hydrogen atoms and one oxygen atom (H20). Elements are made up of only the same type of atom. For example, the element Hydrogen can only contain hydrogen atoms, while the element Carbon can only contain carbon atoms.

Answer:

3.5×10^-4 moles of methane is needed.

Answer:

C. Decomposition of water

Explanation:

A decomposition reaction occurs when one reactant breaks down into two or more products.This can be represented by the general equation: AB → A + B. Examples of decomposition reactions include the breakdown of hydrogen peroxide to water and oxygen, and the breakdown of water to hydrogen and oxygen.

The equation for the decomposition of water; 2H2O --> 2H2+O2

Answer:

Decomposition of water!

Explanation:

I just took the test, hope it helps!

Answer:

7.325 mol.

Explanation:

use the formula n=m/mr

so that makes:

234.4/16*2

which is 7.325 mol.

Answer:

Independent variable

Explanation:

Answer: The rows of the periodic table represent the highest energy level of that element.

The columns represent how many valence electrons that element has.

Groups are the same thing as columns, they represent how many valence electrons am element has.

The blocks of the periodic table represent what sublevel(s) the valence electrons fill.

Explanation: Yes

Answer:

I can help!

Explanation:

Blocks

Atomic symbol is the one- or two-letter symbol for each element.

Atomic number is the number of protons in the nucleus, which determines the order of elements on the periodic table. This is also the total number of electrons in neutral atoms of the element.

Atomic mass is the mass in grams of 1 mole of atoms. Note that 1 mole contains 6.022·1023 atoms.

Groups

The first two groups of the periodic table(Alkali metals and Alkali Earth metals) are the s-block. Note that helium, in the last column of the table, is also part of the s-block. The outermost electrons of these elements are in s orbitals.

The transition metals make up the d-block, with electrons filling d orbitals. The lanthanides and actinides make up the f-block, with electrons filling f orbitals.

Groups 13 through 18,(post transition metals, metalloids, Reactive nonmetals, and Noble gases-)except for helium, make up the p-block. The outermost electrons of these elements are in p orbitals.

Sections

Metals are more likely to lose valence electrons

nonmetals are more likely to accept electrons.

Metalloids may act like metals or nonmetals, either losing or gaining valence electrons depending on the situation.

Transition metals(groups 3-12) behave somewhat differently because they can lose electrons from their outermost s or d orbitals.

Noble gases are the elements in group 18 that don’t tend to react with other elements. Noble gases have completely filled outer electron shells, as you can see because they’re at the end of each period. The electrons in these elements are stable, making the elements unreactive.

Periods and Groups

Groups of elements have similar properties in terms of how they react with other elements.

All elements in a row have the same number of electron shells. Each next element in a period has one more proton and is less metallic than its predecessor.

Hope this helps!!

Answer:

D. that the nucleus is located at the center of the atom

I hope that this helps!

There are several atomic models which explain the structure of atoms. Here the given model of atom is similar to Rutherford's model of atom. The nucleus is located at the center of the atom. The correct option is D.

In Rutherford's atomic model, he bombarded a thin sheet of gold foil with high energy alpha particles and made several observations. He said that most of the space inside the atom is empty. A heavy positively charged body called nucleus is present inside the atom.

The nucleus is capable of repelling and deflecting highly energetic alpha particles and also has a appreciable mass and charge. The volume occupied by the heavy positively charged body must be very very small.

Here in the given model, blue dots are electrons which revolve around the nucleus and the red dot is the nucleus which is present at the centre.

Thus the correct option is D.

To know more about Rutherford's model, visit;

https://brainly.com/question/30366944

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Explanation:

It is because hydrogen is a highly combustible and it reacts explosively when it comes in contact with air. And hence as a result, storing of the hydrogen gas is difficult and is dangerous at the same time.

Answer:

Explanation:

The density of a substance can be found by using the formula

[tex]density = \frac{mass}{volume} \\[/tex]

From the question

mass = 53.137 g

volume = 7.11 cm³

We have

[tex]density = \frac{53.137}{7.11} \\ = 7.473558368...[/tex]

We have the final answer as

Hope this helps you

Answer:

Explanation:

In the scenario that is being described the control group would be the 50 men that have been given the placebo because they are the ones that should not have any effects from the placebo and that is by design. The manipulated variable is the new fat-burning pill because it is the one that the scientists can change and modify to try and achieve the desired results. Lastly, the responding variable are the 50 men who are given the new fat-burning pill because they are the ones that will be responding to the effects of the pill and providing the data needed by the scientists.

Answer:

Temperature of gas is 3.21×10² K

Explanation:

Given data:

Volume of bulb = 400 cm³        (400/1000 = 0.4L)

Pressure of bulb = 200 KPa      (200/101= 1.974 atm)

Number of moles of gas = 0.03 mol

Temperature of gas = ?

Solution:

Formula:

PV = nRT

R = general gas constant = 0.0821 atm.L/ mol.K

1.974 atm × 0.4 L= 0.03 mol ×  0.0821 atm.L/ mol.K × T

0.7896 atm.L = 0.002463 atm.L/K × T

T = 0.7896 atm.L / 0.002463 atm.L/K

T = 321 K   0r 3.21×10² K

Answer:

The answer is the last one

Explanation:

1. Give

2.me

3. Brainliest

4.please

Answer:

Explanation:

I’m not sure friend but my best guess would be 2 and 4. If it’s wrong I’m sorry but that seems the most reasonable to me. Good luck :)

Answer:

mixture

Explanation: