Answer:
Consequently, what happens when gas obtained by heating slaked lime and ammonium chloride is passed through copper sulphate solution? The HCl in the gas mixture will form hydrochloric and the H+ will react with some of the NH3(aq), forming NH4^+, and with some of the SO4^2-, forming HSO4^-.
Explanation:
Physical change -
It refers to any change during any process , where there is no new substance is formed , is referred to as a physical change.
Any change in the state of matter is characterised under physical change.
Chemical change -
It refers to any change in a chemical process , where there is formation of any new substance , is referred to as a chemical change .
From the options given in the question,
1. Apple turning brown , on air exposure , is an example of chemical change .
2. The physical state of mercury is liquid , is an example of physical change .
3. phosphorus burns on exposed to air , is an example of chemical change .
4. The gas Neon is colorless at the room temperature , is is an example of physical change .
Answer:
Empirical CHO2
Molecular C2H2O4
Explanation:
To determine the formulas, firstly, we need to divide the percentage compositions by the atomic masses.
Kindly note that the atomic mass of carbon, oxygen and hydrogen are 12, 16 and 1 respectively. We proceed with the division as follows:
C = 26.7/12 = 2.225
H = 2.2/1 = 2.2
O = 71.1/16 = 4.44375
We then proceed to divide by the smallest value which is 2.2 in this case
C = 2.25/2.2 = 1
H = 2.2/2.2 = 1
O = 4.44375/2.2 = 2
Thus, the empirical formula is CHO2
We now proceed to get the molecular formula as follows
[12+ 1 + 16(2) ]n = 90.04
45n = 90.04
n = 90.04/45 = 2
The molecular formula is :
C2H2O4
Answer:
-241 kJ/mol
Explanation:
Let's consider the reaction of hydrogen with excess oxygen to form water.
2 H₂ + O₂ ⟶ 2 H₂O
When 2.16g of hydrogen reacts with excess oxygen, 258 kJ of heat are released, that is, Q = -258 kJ. Considering that the molar mass of hydrogen is 2.02 g/mol, the change of enthalpy associated with the reaction of 1.00 mol of hydrogen gas is:
ΔH° = -258 kJ/2.16 g × (2.02 g/1.00 mol) = -241 kJ/mol
