Answer:
=1.36kg
Explanation:
First heat is absorbed to melt the ice- latent heat of fusion of ice then heat is absorbed to raise the temperature to 373K
The specific heat capacity of water is 4.187kJ/kg/K while the latent heat of fusion of ice is 2230kJ/kg/K.
Letting the mass of the ice to be =x
x×2230kJ/kg/K + x×4.187kJ/kg/K×100K= 3600kJ
2230x+418.7x=3600
2647.8x=3600
x=1.36 kg
the answer is B. Atmosphere
Barium has a 2+ charge as it is in group 2 in the periodic table and so it has two electrons in its outer shell and chloride has a -1 charge on its chloride ion. So we will need two of the chloride ions as we have a 2+ charge to match the amount of charge on one barium ion- forming barium ion
BaCI2
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.
