General Chemistry Answers

. During a serial dilution, you use 15.0 mL of a standard solution and dilute it to 1.35 L twice. What is the final concentration if the standard solution had a concentration of 0.500 M? 

Find the concentration of all ions present in a 0.223 M solution of PbCl2. (2 marks for solvation, 2 marks for each concentration). 

A student adds 1.15 L of water to 750 mL of a 0.330 M solution of NaCl. What is the concentration of the diluted solution? 

Determine the empirical formula if a compound is made up of 14.0 g Nitrogen and 8.00 g Oxygen. 

Using the average atomic masses for each of the following elements, calculate the mass (in amu) of each of the following samples.

1. 128 carbon atoms
2. Mass = amu
3.  potassium atoms
4. Mass = amu
5.  of lithium atoms
6. Mass =  amu

Merchants usually sell small nuts, washers, and bolts by weight (like jelly beans!) rather than by individually counting the items. Suppose a particular type of washer weighs 0.120 g on the average.

1. What would 62 such washers weigh?
2. g
3. How many washers would there be in 105 g of washers?
4. washers

ACTIVITY 1

Consider the following equation:

Ca(OH)2(s) + 2 HCl(aq) —> CaCl2(aq) + 2 H2O(l)

a) How many liters of 0.100 M HCl is required to completely react with 5.00 grams of calcium hydroxide?

b) If 15.0 grams of calcium hydroxide is combined with 75.0 mL of 0.500 M HCl, how many grams of calcium chloride would be formed?

ACTIVITY 1

Consider the following equation:

Ca(OH)2(s) + 2 HCl(aq) —> CaCl2(aq) + 2 H2O(l)

2. What is the relationship between amino acids and the nitrogenous bases of purines and pyrimidines?

3. What is cloning? Cite its advantages and disadvantages.

Determine all possible ratios for the following balanced chemical equations.

3Fe(s)+4H2O(l) Fe3O4(s)+ 4H2(g)