Answer:
Increase
Explanation:
According to Gay-Lussac Law,
The pressure of given amount of a gas is directly proportional to its temperature at constant volume and number of moles.
Mathematical relationship:
P₁/T₁ = P₂/T₂
If the initial temperature and pressure is standard,
Pressure = 1 atm
Temperature = 273.15 K
then we increase the temperature to 400.0 K, The pressure will be,
1 atm / 273.15 K = P₂/400.0K
P₂ = 1 atm × 400.0 K / 273.15 K
P₂ = 400.0 atm. K /273.15 K
P₂ = 1.46 atm
Pressure is also increase from 1 atm to 1.46 atm.
<span>12.4 g
First, calculate the molar masses by looking up the atomic weights of all involved elements.
Atomic weight manganese = 54.938044
Atomic weight oxygen = 15.999
Atomic weight aluminium = 26.981539
Molar mass MnO2 = 54.938044 + 2 * 15.999 = 86.936044 g/mol
Now determine the number of moles of MnO2 we have
30.0 g / 86.936044 g/mol = 0.345081265 mol
Looking at the balanced equation
3MnO2+4Al→3Mn+2Al2O3
it's obvious that for every 3 moles of MnO2, it takes 4 moles of Al. So
0.345081265 mol / 3 * 4 = 0.460108353 mol
So we need 0.460108353 moles of Al to perform the reaction. Now multiply by the atomic weight of aluminum.
0.460108353 mol * 26.981539 g/mol = 12.41443146 g
Finally, round to 3 significant figures, giving 12.4 g</span>
Answer:
Molar concentration of solution = 0.0056 moles / liter
Explanation:
Looking at the chemical reaction we realize that the precipitate, formed by adding the iron powder, is cooper.
Then for finding the number of moles of precipitated copper:
From the chemical reaction we deduce that moles of Cu equals to moles of in the initial solution.
So molar concentration is defined as:
Answer:
E = 3 × 10¹⁰ J
Explanation:
Mass, m = 100 kg
We need to find energy made by the loss of 100 kg of mass. The formula between the mass and energy is given by :
E = mc²
Where c is speed of light
Putting all the values, we get :
E = 100 kg × (3×10⁸ m/s)²
= 3 × 10¹⁰ J
So, the required energy is 3 × 10¹⁰ J.