Answer:
8.3 kJ
Explanation:
In this problem we have to consider that both water and the calorimeter absorb the heat of combustion, so we will calculate them:
q for water:
q H₂O = m x c x ΔT where m: mass of water = 944 mL x 1 g/mL = 944 g
c: specific heat of water = 4.186 J/gºC
ΔT : change in temperature = 2.06 ºC
so solving for q :
q H₂O = 944 g x 4.186 J/gºC x 2.06 ºC = 8,140 J
For calorimeter
q calorimeter = C x ΔT where C: heat capacity of calorimeter = 69.6 ºC
ΔT : change in temperature = 2.06 ºC
q calorimeter = 69.60J x 2.06 ºC = 143.4 J
Total heat released = 8,140 J + 143.4 J = 8,2836 J
Converting into kilojoules by dividing by 1000 we will have answered the question:
8,2836 J x 1 kJ/J = 8.3 kJ
Adopting the number of avogrado 6.02 * 10²³ / mol
<span>Sodium chloride (table salt)</span> Molar Mass = 58.44 g / mol
We will first have to find the number of moles in 35 grams of the element, like this:
1 mol ----------------- 58.44 g
X ---------------------- 35 g
58.44 * x = 35 * 1
58.44x = 35

X = 0.598904...
X ≈ 0.60<span> mol </span>
Now we will find how many atoms there are in 0.60 mol of this element, like this:
1 mol -------------------- 6.02 * 10²³ atoms
0.60 mol ----------------- X
X = 0.60 * 6.02 * 10²³
This equation is impossible. NaSO4 is non-existent. Did you mean Na2SO4?
Answer:
Volume = 45.62L
Explanation:
Data;
V1 = 54.9L
T1 = 64°C = (64 + 273.15)k = 337.15K
T2 = 7°C = (7 + 273.15)k = 280.15K
V2 = ?
From Charles law,
The volume of a fixed mass of gas is directly proportional to its temperature provided that pressure remains constant
V = KT, K = V / T = V1 / T1 = V2 / T2 = V3 / T3 =.........= Vn / Tn
(54.9 / 337.15) = (V2 / 280.15)
V2 = (54.9 * 280.15) / 337.15
V2 = 45.618L
V2 = 45.62L