What is the mass of 5 moles of carbon? (Ar of Carbon = 12)
2.4 g
12 g
60 g
How many moles water (H2O) are in 90 g of water? (Ar of Hydrogen = 1, Ar of O = 16)
18
5
0.2
How many moles are in 2 g of solid sodium hydroxide (NaOH)? (Ar of Na = 23, Ar of O = 16, Ar of H = 1).
0.05
0.07
80
How many molecules are there in 0.25 moles of methane, CH4? (Assume Avogadro's Constant is 6 x 1023).
1.5 x 1023
2.4 x 1024
1.5
How many atoms are there in 3.4 g of ammonia (NH3)? (Ar of N = 14, Ar of H = 1). Assume Avogadro's constant is 6 x 1023.
1.2 x 1023
4.8 x 1023
How many oxygen atoms are in 1.1 g of carbon dioxide, CO2? (Ar of C = 12 , Ar of O = 16). Assume Avogadro's constant is 6 x 1023.
1.5 x 1022
3 x 1022
4.5 x 1023
How many ions are contained in 9.4g of potassium oxide, K2O? (Ar of K = 39, Ar of O = 16). Assume Avogadro's constant is 6 x 1023.
6 x 1022
1.8 x 1024
1.8 x 1023
What is the reactant that is completely used up in a chemical reaction called?
Excess reactant
Limiting reactant
Limiting product
What mass of hydrogen is produced when 36 g of magnesium reacts completely with excess sulfuric acid? (Ar of Mg = 24; Mr of H2 = 2)
The balanced equation is: Mg(s) + H2SO4(aq) → MgSO4(aq) + H2(g).
3 g
2 g
1 g
If 1.6 g of sulfur combines with 2.4 g of oxygen, how many moles of oxygen will combine with 1 mole of sulfur? (Ar of S is 32; Ar of O is 16)
1
3