Answer:
Explanation:
I’m pretty sure that stories differ because they are not proven and can be easily manipulated. Scientific explanations are proven and are probably fact.
Answer:
ΔH = - 2020.57 kJ/mol
Explanation:
Given that :
mass of propanol = 1.685 g
the molar molar mass = 60 g/mol
Thus; the number of moles = mass/molar mass
= 1.685 g/60 g/mol
= 0.028 g/mol
However ;
ΔH = heat capacity C × Δ T
Given that:
The temperature increases from 298.00 K to 302.16 K.
Then ;
Δ T = 302.16 K - 298.00 K
Δ T = 4.16 K
heat capacity C = 13.60 kJ/K
∴
ΔH = 13.60 kJ/K × 4.16 K
ΔH = 56.576 kJ
The equation of the given reaction can be represented as :
Thus for 0.028 mol of heat liberated; ΔH = 56.576 kJ
For 1 mole of heat liberated now:
ΔH = 56.576 kJ/0.028 mol
ΔH = 2020.57 kJ/mol
SInce , Heat is liberated, the reaction undergoes an exothermic reaction thus;
ΔH = - 2020.57 kJ/mol
Answer:
Molarity of HCl = 1.6M
Explanation:
The chemical reaction equation is;
HCl(aq) + NaOH(aq) —> NaCl(aq) + H2O(l)
Now, molarity = number of moles/volume
Thus, for NaOH, we have;
Number of moles = molarity × volume = 2M × (20/1000) L
Number of moles = 0.04 moles
Using the coefficients in the chemical equation above, we can find the corresponding number of moles for HCl.
Number of moles of HCl = 0.04 moles NaOH × (1 mole of HCl/1 mole of HCl) = 0.04 moles of HCl
Thus;
Molarity of HCl = 0.04/(25/1000)
Molarity of HCl = 1.6M
Answer:
32.711
Explanation:
1 yard = 0.0009144 km
1 week = 168 hrs
6.01 x 10^6 / 168 = 35,773.81 yds/hr
= 32.711 km/hr
Finding percent composition is fairly easy. You only need to divide the mass of an element by the total mass of the compound. We can do this one element at a time.
First, let's find the total mass by using the masses of the elements given on the periodic table.
7 x 12.011 (mass of Carbon) = 84.077
5 x 1.008 (mass of Hydrogen) = 5.04
3 x 14.007 (mass of Nitrogen) = 42.021
6 x 15.999 (mass of Oxygen) = 95.994
Add all of those pieces together.
84.077 + 5.04 + 42.021 + 95.994 = 227.132 g/mol is your total. Since we also just found the mass of each individual element, the next step will be very easy.
Carbon: 84.077 / 227.132 = 0.37016 ≈ 37.01 %
Hydrogen: 5.04 / 227.132 = 0.022189 ≈ 2.22 %
Nitrogen: 42.021 / 227.132 = 0.185 ≈ 18.5 %
Oxygen: 95.994 / 227.132 = 0.42263 ≈ 42.26 %
You can check your work by making sure they add up to 100%. The ones I just found add up to 99.99, which is close enough. A small difference (no more than 0.03 in my experience) is just a matter of where you rounded your numbers.