Date Class
6.
A balanced equation represents the law of mass conservation, and as a re-
sult all of the following are true except
a. the number of moles of products equals the number of moles of reac-
tants
b. the total mass of the products equals the total mass of the reactants
c. the number of atoms in the products equals the number of atoms in the
reactants
d. the states of matter of the products are independent of the states of the
reactants

given:

mass of na = 115 g

excess cl2

to determine:

mass of nacl produced

explanation:

given reaction is-

2na(s) + cl2(g) → 2nacl(s)

since cl2 is in excess, na will be the limiting reagent

as per the reaction stoichiometry na: nacl = 1: 1

i.e. moles of na reacted = moles of nacl formed

now, # moles of na = mass of na/atomic mass

                                  = 115 g/23 g.mol-1 = 5 moles

therefore, moles of nacl = 5

molar mass of nacl = 58 g/mol

mass of nacl = 5 moles * 58 g.mol-1 = 290 g

ans: amount of nacl produced = 290 g

indium, and thallium have three electrons i think

hey there!

mass = 6.75 g

volume =   9 cm³

therefore:

d = mass / volume

d   = 6.75 / 9

d = 0.7 g/cm³

answer b