I need help on this one too I think it might be (b)
Answer:
119.85 grams Br or 120. grams Br (sig figs)
Explanation:
1.50 moles Br 79.90 g Br
--------------------- x ------------------------ = 119.85 grams Br or 120 grams Br (sig figs)
1 mole
yes
Explanation:
the molar mass of a compound is g/mol
Answer:
41.9 g
Explanation:
We can calculate the heat released by the water and the heat absorbed by the steel rod using the following expression.
Q = c × m × ΔT
where,
c: specific heat capacity
m: mass
ΔT: change in temperature
If we consider the density of water is 1.00 g/mol, the mass of water is 125 g.
According to the law of conservation of energy, the sum of the heat released by the water (Qw) and the heat absorbed by the steel (Qs) is zero.
Qw + Qs = 0
Qw = -Qs
cw × mw × ΔTw = -cs × ms × ΔTs
(4.18 J/g.°C) × 125 g × (21.30°C-22.00°C) = -(0.452J/g.°C) × ms × (21.30°C-2.00°C)
ms = 41.9 g
