C is correct.
Please vote my answer brainliest. thanks!
Answer:
The answer is 1.06g.
Explanation:
Analysis of question:
1. Identify the information in the question given.
- volume of HCl is 2 dm3
- pH of HCl is 2.0
2. What the question want?
- mass of Na2CO3 is ?(unknown)
- 3. Do calculation.
- 1st-Write a balanced chemical equation:
Na2CO3 + 2HCl (arrow) 2NaCl + H20 + CO2
- 2nd-Determine the molarity of HCl with the value of 2.0.
pH= -log[H+]
2.0= -log[H+]
log[H+]= -2.0
[H+]= 10 to the power of negative 2(10-2)
=0.01 mol dm-3
molarity of HCl is 0.01 mol dm-3
- 3rd-Find the number of moles of HCl
n=MV
=0.01 mol dm-3 × 2 dm3
=0.02 mol of HCl
- 4th-Find the second mol of it.
Based on the chemical equation,
2.0 mol of HCl reacts with 1.0 mol of Na2CO3
0.02 mol of HCl reacts with 0.01 mol of Na2CO3
<u>N</u><u>a</u>2CO3>a=<u>1</u><u> </u>mol
<u>2</u><u>H</u>Cl>b=<u>2</u><u> </u>mol
mass= number of mole × molar mass
g=0.01 × [2(23)+ 12+ 3(16)]
g=0.01 × 106
# =1.06 g.
Answer:
Acids and bases are used in most many chemical reactions in chemistry . They are responsible for most colour changes in a chemical reaction and are used to adjust the pH of chemical solutions.
Explanation:
First, use the given amount of reactants to calculate the theoretical amount of products that should be formed based on stoichiometry. Next, divide the actual amount of obtained product by that theoretical amount, and multiply by 100%. This gives the percent yield of the reaction.
Answer:
I think first one..........
