General Chemistry Answers

A gas with an initial pressure of 15.7 atm was allowed to expand to a volume of 15.2 L and a new pressure of 6.6 atm. What was the original volume (in L) of the gas?

How many liters of water do I need if I have 60 g of Ca3(PO4)2 to make a .5 M solution

A student is attempting to make up 500.0 mL of a 0.433 M solution of Li₃PO₄ from a stock solution which has a molarity of 1.70 M. How many mL of the stock solution will they need to add to a 500.0 mL volumetric flask to make up the 0.433 M solution?

How many grams of ammonium chloride (NH₄Cl) will you add to 250.mL of water to make a 0.577 M solution?

How much heat, in joules, is absorbed by 500.0 g of water as its temperature is increased from 10.0oC to 85.0oC?  The specific heat of water is 4.184 J/g•oC 

Express the following number in scientific notation. Do NOT include unit in your answer. Please use e to refer to power of 10. For example, 1 x 10^6 should be entered as 1e6, 4.5 x 10^-7 should be entered as 4.5e-7.

Wavelength of orange light is 0.00000060 m, scientific notation is ______ m.

8) Predict the mass of hydrogen gas produced when 2.73 g of aluminum reacts in a single replacement reaction with excess sulphuric acid.

2Al + 3H2SO4 -> 3H2 + Al2(SO4)3

7) Aluminum oxide is decomposed using electricity to produce aluminum metal. How many grams of aluminum metal can be produced from 100.0 g of Al2O3?

2Al2O3 -> 2Al + 3O2

6) Iron metal is produced in a blast furnace by reaction of iron (lll) oxide and coke (pure carbon). If 25.0 moles of pure Fe2O3 is used, how many grams of iron can be produced? The balanced chemical equation for the reaction is:

Fe2O3 + 3C -> 2Fe + 3CO

1. Solutions of iron (lll) chloride, FeCl3, are used in photoengraving and to make ink. This compound can be made be the following reaction:

2F + 3Cl2 -> 2FeCl3

a. How many grams of Fe are needed to combine with 4.5 moles of Cl2?

b. If 240 g of Fe is to be used in this reaction, with adequate Cl2, how many moles of FeCl3 will be produced?