Question 4 of 20 A student is performing experiments on a particular substance. Which
statement is an observation of a chemical property of the substance?
A. Its viscosity decreases.
B. It boils.
C. Electricity passes through it.
D. It reacts with acid.
SUBMIT

D

Explanation:

Reacting with acid is the only chemical property out of the 4 options. The rest are physical

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