A covalent bond? Not sure how much detail you want, sorry
Step 1 - Discovering the ionic formula of Chromium (III) Carbonate
Chromium (III) Carbonate is formed by the ionic bonding between Chromium (III) (Cr(3+)) and Carbonate (CO3(2-)):

Step 2 - Finding the molar mass of the substance
To find the molar mass, we need to multiply the molar mass of each element by the number of times it appears in the formula of the substance and, finally, sum it all up.
The molar masses are 12 g/mol for C; 16 g/mol for O and 52 g/mol for Cr. We have thus:

The molar mass will be thus:

Step 3 - Finding the percent composition of carbon
As we saw in the previous step, the molar mass of Cr2(CO3)3 is 284 g/mol. From this molar mass, 36 g/mol come from C. We can set the following proportion:

The percent composition of Carbon is thus 12.7 %.
1. carbon lies in the 2nd period where silicon in the third period.
2. carbon is a non metal whereas silicon is a metalloid.
3. there are only 3 isotopes of carbon and 23 isotopes of silicon
4. size of silicon atom is larger
5. silicon is heavier than carbon.
Answer:

Explanation:
To solve this problem, we can use the Combined Gas Laws:

Data:
p₁ = 2.02 atm; V₁ = 736 mL; n₁ = n₁; T₁ = 1 °C
p₂ = ?; V₂ = 416 mL; n₂ = n₁; T₂ = 82 °C
Calculations:
(a) Convert the temperatures to kelvins
T₁ = ( 1 + 273.15) K = 274.15 K
T₂ = (82 + 273.15) K = 355.15 K
(b) Calculate the new pressure
