CHM Test Quizzes Answers 2025/2026

1. How many aluminum atoms are there in 52 g of Al2S3
   4.2 x 10^23
   1.6 x 10^21
   2.1 x 10^23
   1.1 x 10^21
   6.3 x 10^23 wrong
   52g Al2S3 = 1 mol Al2S3 = 2 mol Al = 6.02 x 10^23 Al = 4.2 x 10^23 Al atoms
    150g Al2S3 1 mol Al2S3 1 mol Al
   2. A 15-g sample of lithium is reacted with 15 g of fluorine to form lithium fluoride: 2Li + F2 ==> 2[LiF].
   After the reaction is complete, what will be present?
   a) 2.16 mol lithium fluoride only
   b) 0.789 mol lithium fluoride only
   c) 2.16 mol lithium fluoride and 0.395 mol fluorine
   d) 0.789 mol lithium fluoride and 1.37 mol lithium
   e) none of these
   3. What is the mass percent of carbon in the compound c6h6o2
   a) 5.5%
   b) 70.9%
   c) 65.5%
   d) 29.1%
   e) 14.3%
   4. How many aluminum atoms are there in 52 g of Al2S3
   4.2 x 10^23
   1.6 x 10^21
   2.1 x 10^23
   1.1 x 10^21
   6.3 x 10^23 wrong
   52g Al2S3 = 1 mol Al2S3 = 2 mol Al = 6.02 x 10^23 Al = 4.2 x 10^23 Al atoms
    150g Al2S3 1 mol Al2S3 1 mol
   5. if 48.8g of o2 is mixed with 48.8g of h2 and the mixture is ignited, what is the maximum mass of water
   that may be produced?
   a) 439 g
   b) 54.9 g correct
   c) 48.8 g
   d)
   e)
   2H2 + O2 -> 2H2O
   48.8g O2 = 1 mol O2 = 2 mol H2O = 3.05 mol H2O
    32g O2 1 mol O2
   48.8g H2 = 1 mol H2 = 2 mol H2O = 24.4 mol H2O
    2 g H2 2 mol A2
   3.05 mol H2O = 18 g H2O = 59.9 g H2O
    1 mol
   6. 2Al(s) + 6HCl(aq)
    
    2AlCl3
   (aq) + 3H2
   (g)
   According to the equation above, how many grams of aluminum are needed to react with 3.83 mol of
   hydrochloric acid?
   A] 310 g
   B] 46.6 g
   C] 34.4 g correct
   D] 3.83 g
   E] 103.3 g
   3.83 mol HCl = 2 mol Al = 27 g Al = 34.4g
    6 mol HCl 1 mol Al