Answer:
The value of the heat capacity of the Calorimeter = 54.4
Explanation:
Given data
Heat added Q = 4.168 KJ = 4168 J
Mass of water = 75.40 gm
Temperature change = ΔT = 35.82 - 24.58 = 11.24 ° c
From the given condition
Q = ΔT +
ΔT
Put all the values in above equation we get
4168 = 75.70 × 4.18 × 11.24 + × 11.24
611.37 = × 11.24
= 54.4
This is the value of the heat capacity of the Calorimeter.
<u>Complete Question:</u>
what mass of zinc is needed to react with 23.1 g of phosphoric acid according tot he equation?
3 Zn + 2 H₃PO₄ = 3 H₂ + Zn₃(PO₄)₂
<u>Answer:</u>
22.98 g, the mass of zinc (Zn) is needed to react with 23.1 g of phosphoric acid according to the given equation.
<u>Explanation:</u>
Given chemical reaction:
3 Zn + 2 H₃PO₄ = 3 H₂ + Zn₃(PO₄)₂
If the substance’ molecular weight is the number of grams required per mole, the number of moles expressed as a given quantity of substances shall correspond to the grams of that substance divided by the molecular weight. Hence,
To find no. of moles of phosphoric acid:
Given:
mass of phosphoric acid = 23.1 g
molar weight of of phosphoric acid = 97.994 = 98 g/mole
Therefore,
no. of moles of phosphoric acid
Look into the given chemical reaction and divide as the following:
If 2 moles of H₃PO₄ reacts with 3 moles of Zn then 0.2357 moles of H₃PO₄ reacts with X moles of Zn. Then,
Now, calculate mass of zinc as follows, we know
molar mass of zinc is 65 g/mol
Mass of zinc = 22.98 g