You have to calculate the oxidation estates of the atoms in each compound.
I will start with K2Cr2O7 because I believe that Cr is the best candidate to reduce its oxidation number in 3 units.
In K2Cr2O7:
- K has oxidation state of 1+, then K2 has a charge of 2* (1+) = 2+.
- O has oxidation state of 2*, then O7 has a charge of 7* (2-) = 14-.
That makes that Cr2 has charge of 14 - 2 = +12, so each Cr has +12/2 = +6 oxidation state.
In Cr2O3:
- O has oxidation state of 2-, then O3 has charge 3 * (2-) = - 6
- Then, Cr2 has charge 6+, and each Cr has charge 6+ / 2 = 3+.
So, we have seen that Cr reduced its oxidation state in 3 units, from 6+ to 3+.
Answer: Cr has a change in oxidation number of - 3.
Answer:
The correct answer is -
1. a) The bubbles will shrink, some may vanish.
2. a) Can A will make a louder and stronger fizz than can B.
Explanation:
In the first question, it is given that the bottle is not opened and therefore, squeezing the bottle filled with a carbonated drink will increase the pressure on the carbonated liquid which forces the bubbles to dissolve or displace or vanish as it moves to empty space.
Thus, the correct answer would be - The bubbles will shrink, some may vanish
In the second question, there are two different conditions for two different unopened cans of carbonated water that are different temperatures one at the garage with higher temperature and one in the fridge at low temperature. As it is known that higher the temperature less will be solubility of gas in liquid so gas in can A will be less soluble which means it has more gas and it will make louder and stronger fizz than B which was stored at low temperature.
thus, the correct answer would be - Can A will make a louder and stronger fizz than can B.
The states of matter is solid,liquid and gas & you go from there.
True.
Every environment and ecosystem will include these factors.