Answer:
the number of atoms
Explanation:
atoms are never created not destroyed
<u>Answer:</u> The mass of water produced in the reaction is 97.2 grams
<u>Explanation:</u>
We are given:
Moles of calcium hydroxide = 2.70 moles
The chemical equation for the reaction of calcium hydroxide and HCl follows:
By Stoichiometry of the reaction:
1 mole of calcium hydroxide produces 2 moles of water
So, 2.70 moles of calcium hydroxide will produce = 
of HCl
To calculate mass for given number of moles, we use the equation:
Molar mass of water = 18 g/mol
Moles of water = 5.40 moles
Putting values in above equation, we get:
Hence, the mass of water produced in the reaction is 97.2 grams
Answer:
0.875 time.
Explanation:
The length of plastic water bottles are bought in the United States every day = (the no. of plastic water bottles are bought every day)(length of each bottle) = (140.0 million bottle)(0.25 m) = 35.0 million meter.
The length of the equator of the earth = 40.0 million meter.
∴ The times can the Earth's equator be circled by a line of plastic bottles used in the United States every day = (The length of plastic water bottles are bought in the United States every day)/(The length of the equator of the earth) = (35.0 million meter)/(40.0 million meter) = 0.875 times.
Answer:
Molarity of 
solution is 0.612 mol/L
Explanation:
Number of moles of a substance = (mass of substance)/(molar mass of the substance)
Molar mass of = 214 g/mol
So, 562 g of = 
moles of = 2.63 moles of
Molarity of a solution = (number of moles of solute in solution)/(total volume of solution in liter)
Here solute is and solvent is water
Total volume of solution is 4.30 L
So, molarity of solution = 
= 0.612 mol/L
Answer:
c. 0.2 M HNO₃ and 0.4 M NaF
.
Explanation:
A buffer is defined as the mixture of a weak acid with its conjugate base or a weak base with its conjugate acid.
A weak acid or weak base are defined as an acid or base that partially dissociates in aqueous solution. in contrast, a strong acid or base are acids or bases that is dissociated completely in water.
Thus:
a. 0,2M HNO₃ and 0.4 M NaNO₃. This is a mixture of a strong acid with its conjugate base. <em>IS NOT </em>a buffer.
b. 0.2 M HNO₃ and 0.4 M HF
. This is a mixture of two strong acids. <em>IS NOT </em>a buffer.
c. 0.2 M HNO₃ and 0.4 M NaF
. NaF is the conjugate base of a weak acid as HF is.
The reaction of HNO₃ with NaF is:
HNO₃ + NaF → HF + NaNO₃
That means that in solution you will have a weak acid (HF) with its conjugate base (NaF). Thus, this mixture <em>IS </em>a buffer.
d. 0.2 M HNO₃ and 0.4 M NaOH. This is the mixture of a strong acid with a strong base, thus, this <em>IS NOT </em>a buffer.
I hope it helps!
