Answer: 11.2 L of 
at 273K and 202kPa
Explanation:
According to ideal gas equation:
P = pressure of gas = 202 kPa = 1.99 atm ( 1kPa= 0.0098 atm)
V = Volume of gas = 11.2 L
n = number of moles = ?
R = gas constant =
T =temperature =
According to avogadro's law, equal number of moles occupy equal volumes and contain equal number of molecules at same temperature and pressure conditions.
As 11.2 L of at 273K and 202kPa will have same moles as 11.2L of He (g) at 273K and 202kPa, thus they have same number of molecules.
Answer:
<h3>The answer is 7.14 g/mL</h3>
Explanation:
The density of a substance can be found by using the formula
From the question
mass = 10 g
volume = final volume of water - initial volume of water
volume = 52.1 - 50.7 = 1.4 mL
We have
We have the final answer as
<h3>7.14 g/mL</h3>
Hope this helps you
Answer:
Explanation:
To solve this problem, we must understand the relationship between mass of a substance and the number of atoms.
Atoms are the smallest indivisible particles of any matter. A substance can be made up of several number of atoms in their space.
The mass of any substance is a function of the amount of atoms its contains.
The mass of a substance is related in chemistry to the amount of atoms its contains using the parameter called the number of moles.
A mole is the amount of substance that contains the Avogadro's number of particles. This number is 6.02 x 10²³ particles. The particles here can be protons, neutrons, electrons, atoms e.t.c.
Now,
Number of moles = 
Molar mass of copper = 63.6g/mole
Number of moles = 
= 0.03mole
Since 1 mole of a substance contains 6.02 x 10²³atoms
0.03 mole of copper will contain 0.03 x 6.02 x 10²³atoms
= 1.89 x 10²² atoms
He needs to add 1.89 x 10²² atoms to make 2g of the sample.
Answer: Statements (A), and (C) are correct.
Explanation:
The statements that are true are as follows.
- Particles in a liquid need to move more slowly in order to freeze.
When a liquid freezes the molecules get attracted towards each other. This attraction of particles occurs slowly. Hence, this statement is true.
- Attractive forces between the particles in a liquid are broken when a liquid boils.
When temperature is raised, the molecules in a liquid gains kinetic energy and start to move quickly in random directions. As a result, liquid state changes to gaseous state. Hence, this statement is true.
If the attractive force between gas molecules have to be increased, they should be moving slower instead because moving faster does not help attracting molecules together.
Hence, the statement particles in gas move fast enough to make more attractive forces when the gas condenses is not true.
