Answer : The pressure of the hydrogen gas exert before its volume was decreased will be, 2.28 atm
Explanation :
According to the Boyle's law, the pressure of the gas is inversely proportional to the volume of the gas at constant temperature of the gas and the number of moles of gas.
or,
or,
where,
= initial pressure of the gas = ?
= final pressure of the gas = 5.09 atm
= initial volume of the gas = 12.16 L
= final volume of the gas = 5.45 L
Now put all the given values in this formula, we get the initial pressure of the gas.
Therefore, the pressure of the hydrogen gas exert before its volume was decreased will be, 2.28 atm
The question is incomplete, the complete question is;
A 31 g sample of a compound that contains only the elements C,H and N is completely burned in O2 to produce 44.0 g of CO2, 45.0 g of H2O, and 92.0 g of NO2. Determine the empirical formula of the compound.
Answer:
CH5N2
Explanation:.
Mass of C = 44.0g/44.0 g/mol = 1 mol * 1 = 1 mole of C
Mass of H = 45.0 g/18 g/mol = 2.5 moles * 2 = 5 moles of H
Mass of N = 92.0 g/46 g/mol = 2 moles * 1 = 2 moles of N
Dividing through by the lowest mole ratio;
1/1, 5/1, 2/1
1 : 5 : 2
Hence the empirical formula is;
CH5N2
Molar mass of Benzoic Acid =122.1gmol
−1
Morality of Ba(OH)
2=0.120mol/L2E6H5COOH+Ba(OH) 2→2H2+Ba(C6H5COO) 2
From the given Molar mass, we find the number of moles of Benzoic acid and Barium
hydrocide.
Moles of Benzoic acid = MolarMass
GivenMass= 122.10.2=0.00163 Moles
Moles of Ba(OH) 2= 20.00163=0.000815
Now, Morality of Ba(OH)
2= LitreofSolutionmolesofsolute=0.120M is required 1 Litre,
So 0.000815M is required in
0.1201 ×0.000815 =0.00679=6.
Answer:
C
Explanation:
The atom has an electron configuration of 1s²2s²2p⁶3s²3p⁵.
The total numbe of electrons present in the shell is 17 electrons. To determine the group of the atom, we have to check what orbital did the last electron stop.
If it's in S-orbital, then we automatically knows it's an s-block element which could either be group 1 or 2 and can still be furthered down to know which group it's in.
But in this case, the last electron is in s-orbital. To determine the group number of p-orbitals, we'll have to consider the preceding s-orbital and add it to it, then count it in 10s.
For example, if the last two orbital is 3s² 3p¹, 2 + 1 = 3, add ten (10) to it = 13. Hence the element is in group 13.
In this case, we have 3s² 3p⁵ = 2 + 5 = 7 + 10 = 17.