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.
Chemical bonds hope this helps<span>
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Answer: The given question is incomplete. The complete question is:
At a certain temperature the rate of this reaction is second order in 
with a rate constant of 
. 
Suppose a vessel contains at a concentration of 0.100 M Calculate how long it takes for the concentration of to decrease to 0.0240 M. You may assume no other reaction is important. Round your answer to 2 significant digits.
Answer: It takes 0.93 seconds for the concentration to decrease to 0.0240 M.
Explanation:
Integrated rate law for second order kinetics is given by:
= initial concentration = 0.100 M
a= concentration left after time t = 0.0240 M
k = rate constant =
t = time taken for decomposition = ?
Thus it takes 0.93 seconds for the concentration to decrease to 0.0240 M.
