C) a standard cubic foot of natural gas carries with it about 1.1 x 106 j of energy. natural gas currently costs about $16.25 per thousand cubic feet. how many joules of energy in the form of natural gas can you get for a dollar?

d) a short ton of coal holds about 2.24 x 107 j of energy and costs about $56.45 per short ton. how many joules of energy in the form of coal can you get for a dollar?

67692.31 J

396811.337 J

Explanation:

(a) The cost of standard cubic foot of natural gas = $16.25

The energy related to standard cubic foot of natural gas =

Thus, As according to the question,

$16.25 of natural gas have of energy.

$1 of natural gas have of energy.

The amount of energy = 67692.31 J

(b) The cost of one short ton of coal = $56.45

The energy related to the short ton of coal =

Thus, As according to the question,

$56.45 of coal have of energy.

$1 of coal have of energy.

The amount of energy = 396811.337 J

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

1 is the answer to this problem