General Chemistry Answers

Molar mass of zinc

How many moles of gallium chloratenGa(ClO02)must react in order to produce 674 kj of energy according to the following reaction?

2Ga(ClO3)2------>2GaCl03+902H =-130.4Kj

1. A compound has 45 g of iron, 6 g of oxygen, and 3 g of sulfur. Find the percent of each element.

2. A compound has 3 g of sodium and 5 g of bromide. Find the percent of each.

a- Combustion of 13.5 g of sample of an hydrocarbon yields 24.41 g CO, and 14.49 g H2O. The molar mass of the compound is 246 g/mol. What are the empirical and molecular formulas?

b- Balance the combustion equation using the molecular formula.

A volatile compound with a mass of 0.8822 grams is placed in an evacuated 0.250 L flask. The flask is heated to evaporate the compound. At 99C, the pressure in the flask is 1.25 atm. What is the molar mass of the compound?

Choose the compound(s) that can act as bases.

Explain why chlorine (Cl₂) is a gas at room temperature, but sodium chloride (NaCl) is

      a solid at room temperature.

How much energy is required to raise the temperature of 250ml of water in a 500g kettle that is 100% iron from 20°C to 99°C?

A 4.0520g sample of HCl, sp. Gr 11.18,

required 44.15ml of 0.9035Mof Sodium

Hydroxide in titration, compute for

percent purity.

a.   How many moles of NaAlO₂ is produced if 126.4 g of NaOH reacts completely?