An unknown substance has a volume of 15. 8 cm 3 and a mass of 2 grams. Use the chart above to identify the unknown substance. What is the substance?
a.
iron
b.
silver
c.
water
d.
gold

21. consider the following chemical reaction: n2+ o2 2 no if 10.0 g of n2 reacts with excess oxygen then how many grams of no can be formed? a) 10.7 g b) 21.4 g c) 32.9 g d) 42.8 g page 4 of 8

What is the formula for the compound dinitrogen pentoxide? a. n4o5 b. n5o4 c. n4o6 d. n5o2 e. n2o5

Which statement characterizes synthetic polymers? a. they come from animals and plants. b. they are found in nature. c. they are made in a lab. d. they are components of starch.