Answer:
13.20 litres
Explanation:
use pascal's law of volume and temperature
You must remember that oxidation number of hydrogen in acids is always +1, oxidation number of oxygen in oxides & acids is always -2... metals has always oxidation number on plus!
group NO3 comes from HNO3...and oxidation number of whole acid group is always on minus and equal to the amount of hydrogen atoms in this acid... so oxidation number of NO3 = -1
we have 2 NO3 groups so 2*(-1) = -2 and that is the reason why oxidation number of Fe in this formula must be +2... because sum of all elements always gives 0!
Now we could count of oxidation number for nitrogen... we write HNO3 and start counting from right to left:
3*(-2) from oxygens + 1 from hydrogen = -5
so nitrogen must have +5 oxidation number... because sum all in formula must be 0.
Answer: 123 g
Explanation: Q =It = nzF. For Ca^2+ z= 2, t = 5.5 x 3600 s and I = 30.0
And F= 96485 As/mol
Amount of moles is n = It /zF = 3.078 mol , multiply with atomic mass 40.08 g/mol
First, we have to see how K2O behaves when it is dissolved in water:
K2O + H20 = 2 KOH
According to reaction K2O has base properties, so it forms a hydroxide in water.
For the reaction next relation follows:
c(KOH) : c(K2O) = 1 : 2
So,
c(KOH)= 2 x c(K2O)= 2 x 0.005 = 0.01 M = c(OH⁻)
Now we can calculate pH:
pOH= -log c(OH⁻) = -log 0.01 = 2
pH= 14-2 = 12
Answer:
C
Explanation:
This is essentially one of the several safety measures in the chemical laboratory. This particular approach is one used in the case of fire eventualities.
A is wrong
This is because in the advent of a fire incident, it is necessary to evacuate the building as a whole. Meeting in the hallway is still within the building which is not the right thing to do when there’s a fire outbreak. Occupants are expected to leave the building immediately
B. Is also wrong. Taking time to pack your belongings might make you be caught in the inferno. It is expected that you leave the building at once
