Answer:
B. 4 ml
Explanation:
Volume displacement of the hammer = volume volume of water when the hammer was placed into the cylinder - volume of water only before the hammer was placed into the cylinder.
Volume volume of water when the hammer was placed into the cylinder = 69 ml
Volume of water only before the hammer was placed into the cylinder = 65 ml
Volume displacement of the hammer = 69 ml - 65 ml = 4 ml
No one is 100% sure when particles of matter originated however scientist believe it had to be some time before the Big Bang
25.9 kJ/mol. (3 sig. fig. as in the heat capacity.)
<h3>Explanation</h3>
The process:
.
How many moles of this process?
Relative atomic mass from a modern periodic table:
- K: 39.098;
- N: 14.007;
- O: 15.999.
Molar mass of
:
.
Number of moles of the process = Number of moles of
dissolved:
.
What's the enthalpy change of this process?
for
. By convention, the enthalpy change
measures the energy change for each mole of a process.
.
The heat capacity is the least accurate number in these calculation. It comes with three significant figures. As a result, round the final result to three significant figures. However, make sure you keep at least one additional figure to minimize the risk of rounding errors during the calculation.
Answer: 
Explanation:
Given : Sample size : n= 30 , it means it is a large sample (n≥ 30), so we use z-test .
Significance level : 
Critical value: 
Sample mean : 
Standard deviation : 
The formula to find the confidence interval is given by :-

i.e. 
i.e. 

Hence, the 95% confidence interval for the mean mpg in the entire population of that car model = 
Balanced equation :
Cu(NO₃)₂(aq) + 2KOH(aq) → Cu(OH)₂(s) + 2KNO₃(aq)
Balancing a chemical equation :
A chemical equation shows us the substances involved in a chemical reaction - the substances that react (reactants) and the substances that are produced (products). In general, a chemical equation looks like this:
Reactant →Product
According to the law of conservation of mass, when a chemical reaction occurs, the mass of the products should be equal to the mass of the reactants. Therefore, the amount of the atoms in each element does not change in the chemical reaction. As a result, the chemical equation that shows the chemical reaction needs to be balanced. A balanced chemical equation occurs when the number of the atoms involved in the reactants side is equal to the number of atoms in the products side.
Learn more about balanced equation :
brainly.com/question/15355912
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