Answer:b
Explanation: it’s in the picture just go counterclockwise
Answer:
39.3%
Explanation:
CaF2 + H2SO4 --> CaSO4 + 2HF
We must first determine the limiting reactant, the limiting reactant is the reactant that yields the least number of moles of products. The question explicitly says that H2SO4 is in excess so CaF2 is the limiting reactant hence:
For CaF2;
Number of moles reacted= mass/molar mass
Molar mass of CaF2= 78.07 g/mol
Number of moles reacted= 11g/78.07 g/mol = 0.14 moles of Calcium flouride
Since 1 mole of calcium fluoride yields two moles of 2 moles hydrogen fluoride
0.14 moles of calcium fluoride will yield 0.14×2= 0.28 moles of hydrogen fluoride
Mass of hydrogen fluoride formed (theoretical yield) = number of moles× molar mass
Molar mass of hydrogen fluoride= 20.01 g/mol
Mass of HF= 0.28 moles × 20.01 g/mol= 5.6 g ( theoretical yield of HF)
Actual yield of HF was given in the question as 2.2g
% yield of HF= actual yield/ theoretical yield ×100
%yield of HF= 2.2/5.6 ×100
% yield of HF= 39.3%
Answer:
See below
Step-by-step explanation:
heat gained by metal + heat lost by water = 0
m₁C₁ΔT₁ + m₂C₂ΔT₂ = 0
C₁ = -(m₂C₂ΔT₂)/(m₁ΔT₁)
The factors determining C₁ are
- mass of water
- temperature change of water (T_f - Ti)
- mass of metal
- temperature change of metal (T_f - Ti)
Any factor that makes the numerator higher or the denominator lower than what you thought, will give a calculated C₁ that is too high (and vice versa).
The major sources of uncertainty are probably in determining the temperatures, especially the initial and final temperatures of the metal. However, you will have to decide what the principal factors were in your experiment.
For example, did the metal have a chance to cool during the transfer to the calorimeter? How easy was it to determine the equilibrium temperature, etc?
Factors Affecting the Calculation of Specific Heat Capacity
<u> Too Low </u> <u> Too high </u>
Water Water
Mass less than thought Mass more than thought
Ti lower Ti higher
T_f higher T_f lower
Metal Metal
Mass more than thought Mass less than thought
Ti higher Ti lower
To answer the question above, let us a basis of the 1000 mL or 1 L.
volume = (0.9928 g/mL)(1000mL) = 992.8 g
Then, determine the mass of the alcohol by multiplying the total mass by the decimal equivalent of 5%.
mass of alcohol = 0.05(992.8 g) = 49.64 g
Then, determine the number of moles of ethyl alcohol by dividing the mass of alcohol by the molar mass (46 g/mol).
n = 49.64 g/ (46 g/mol) = 1.08 mol
Then, divide the number of moles by the volume (our basis is 1 L)
molarity = 1.08 mol/ 1 L = 1.08 M
1: it is +2
2: it is +6
(Make this brainliest answer please)
