5 6
A thermometer is placed in water in order to measure the water 's temperature. What would cause the liquid in the
thermometer to rise?
TUERE
40:
The molecules in the water move closer together.
The molecules in the thermometer's liquid spread apart.
The kinetic energy of the water molecules decreases.
The kinetic energy of the thermometer's liquid molecules decreases.

The molecules in the thermometer’s liquid spread apart.

Explanation:

passing a magnet thought the

mixture , because iron gets attracted to magnet .

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