A metal sample is heated and placed into the water in a calorimeter at room temperature. Which statement best describes how the calorimeter can be used to determine the specific heat capacity of the metal sample?

A) Energy transfers to the metal from the water and calorimeter until they are all at room temperature.
B) Energy transfers from the metal to the water and calorimeter until they are all at room temperature.
C) Energy transfers to the metal from the water and calorimeter until they all reach a single temperature.
D) Energy transfers from the metal to the water and calorimeter until they all reach a single temperature.

D

Explanation:

Energy transfers from the metal to the water and calorimeter until they all reach a single temperature.

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