Answer:
6.82g
0.59moles
Explanation:
1. What is the mass sample of 0.0500 moles of zinc chloride ?
Given parameters:
Number of moles ZnCl₂ = 0.05moles
Unknown:
Mass of the sample = ?
Solution:
To find the mass of a substance using the number of moles, it would be pertinent to understand what mole is.
A mole is a substance that contains the avogadro's number of particles.
It relates to the mass using the expression below;
Mass of a substance = number of moles x molar mass
Molar mass of ZnCl₂;
Atomic mass of Zn = 65.4g/mol
Cl = 35.5g/mol
Molar mass = 65.4 + 2(35.5) = 136.4g/mole
Mass of a substance = 0.05 x 136.4 = 6.82g
2. How many moles of potassium sulfide are in a 65.50g sample?
Given parameters:
Mass of K₂S = 65.5g
Unknown:
Number of moles = ?
Solution:
The number of moles of any substance is related to mass using the expression below;
Number of moles = 
Molar mass of K₂S = 2(39) + 32 = 110g/mol
Number of moles = 
= 0.59moles
Answer:
Lead (II) Chromate and Barium Chromate
Explanation:
Answer:
1.3 × 10³ cm³
Explanation:
The gas occupies a volume of V₁ = 310 cm³ under standard temperature and pressure (STP), that is, T₁ = 273.15 K and P₁ = 1.0 atm. In order to find the volume V₂ under different conditions we can use the combined gas law formula.
Answer:
The number of moles of O atom in 
mol of 
= 1.6
Explanation:
1 molecule of contains 2 atoms of O
So, 
molecules of contains 
atoms of O.
We know that 1 mol of an atom/molecule/ion represents 
numbers of atoms/molecules/ions respectively.
So, molecules of is equal to 1 mol of .
atoms of O is equal to 2 moles of O atom.
Hence, 1 mol of contains 2 moles of O atom.
Therefore, mol of contains 
moles of O atom or 1.6 moles of O atom.
The addition of heat energy to a
system always causes the temperature of that system to increase. This is always
true because you are adding heat of a substance to increase its temperature. For example, you are going
to drink a cup of coffee. And you wanted it hot to boost your attention. So you
have to use hot water. In order for your water to become hot or warm, you need
boil it in a kettle. Note that you are going to use an electric stove. The
electric stove gets it energy from the source giving it a hotter temperature to
the water in the kettle. You are applying heat energy to warm the water. So,
the statement is true.
