Answer:
All three are present
Explanation:
Addition of 6 M HCl would form precipitates of all the three cations, since the chlorides of these cations are insoluble: .
- Firstly, the solid produced is partially soluble in hot water. Remember that out of all the three solids, lead(II) choride is the most soluble. It would easily completely dissolve in hot water. This is how we separate it from the remaining precipitate. Therefore, we know that we have lead(II) cations present, as the two remaining chlorides are insoluble even at high temperatures.
- Secondly, addition of liquid ammonia would form a precipitate with silver: ; Silver hydroxide at higher temperatures decomposes into black silver oxide: .
- Thirdly, we also know we have in the mixture, since addition of potassium chromate produces a yellow precipitate: . The latter precipitate is yellow.
Explanation:The five major branches of chemistry are organic, inorganic, analytical, physical, and biochemistry.
...
Sub-branches of physical chemistry include:
Photochemistry — the study of the chemical changes caused by light.
Surface chemistry — the study of chemical reactions at surfaces of substances
If it gains an electron it will be negatively charged and if it loses an electron it will be positively charged
Answer:
Q = -897 kJ/mol
Explanation:
From the given information:
The heat released Q = -65.9 kJ
To start with the molar mass of = 2 × (molar mass of H) + 2 × (molar mass of O)
= (2 × 1.008) + (2 × 16.0 )
= 34.016 g/mol
However, given that:
mass of 2.50 g
The number of moles of =
Finally; Using the formula:
Q = -897 kJ/mol