The answer would be choice B because the energy decreased by 20 J
Answer:
i think it is all atoms of all elements are exactly alike and have the same mass
Explanation:
Answer:
b) 
The confidence interval for this case is given (6.21, 6.59)
So we can conclude at 95% of confidence that the true mean for the PH concentration is between 6.21 and 6.59 moles per liter
c) Since the confidence interval not contains the value 7 we reject the hypothesis that the true mean is equal to 7. And the same result was obtained with the t test for the true mean.
Explanation:
We assume that part a is test the claim. And we can conduct the following hypothesis test:
Null hypothesis: 
Alternative hypothesis 
The statistic is to check this hypothesi is given by:

We know the following info from the problem:

Replacing we got:

And the p value would be:

Since the p value is very low compared to the significance assumed of 0.05 we have enough evidence to reject the null hypothesis that the true mean is equal to 7 moles/liter
Part b
The confidence interval is given by:

The confidence interval for this case is given (6.21, 6.59)
So we can conclude at 95% of confidence that the true mean for the PH concentration is between 6.21 and 6.59 moles per liter
Part c
Since the confidence interval not contains the value 7 we reject the hypothesis that the true mean is equal to 7. And the same result was obtained with the t test for the true mean.
Answer:
4.86 moles of HCl
Explanation:
1. First write the balanced chemical equations involved in the process:


2. Calculate what amount of
is formed in the first reaction.

As the yield of each reaction is 90.0%, the amount of
produced is the following:

3. Calculate the amount of HCl produced.

The total amount of HCl produced with a 90.0% yield is:
