Answer:
6.02×10^23 atoms
Explanation:
Avogadros constant is a number that states the amount of atoms in one mole of a substance which is 6.02×10^23 to 3 significant figures.
Answer:
The volume is 214, 3 ml
Explanation:
We calculate the weight of 1 mol of NH4OH:
Weight 1 mol NH4OH= Weight N + (Weight H) * 5 + Weight 0
Weight 1 mol NH4OH= 14g + 1 g* 5 + 16g = 35 g/mol
1 mol NH4OH-----35 g
0,6mol NH4OH----X=(0,6mol NH4OHx 35 g)/1 mol NH4OH= 21 g
We have 0,6 mol in 1000ml of solution (0,600 M)
21g NH4OH-----------1000ml
4,50 g NH4OH------x= (4,50 g NH4OH x 1000ml)/21 g NH4OH= 214, 2857143 ml
Answer:
Cr(OH)2(s), Na+(aq), and NO3−(aq)
Explanation:
Let is consider the molecular equation;
2NaOH(aq) + Cr(NO3)2(aq) -----> 2NaNO3(aq) + Cr(OH)2(s)
This is a double displacement or double replacement reaction. The reacting species exchange their partners. We can see here that both the sodium ion and chromium II ion both exchanged partners and picked up each others partners in the product.
Sodium ions and nitrate ions now remain in the solution while chromium II hydroxide which is insoluble is precipitated out of the solution as a solid hence the answer.
There are about 2.2 pounds per Kg. therefore, .25 lbs, or 1/4 lbs is about .113 kg. of butter
there are about 1000 g per kg, so .113×1000 = 113 grams of butter.
Finally, there are 1000 mg. in every gram, so 113 ×1000= 113,000 mg of butter.
Explanation:
The reaction equation will be as follows.
![H_{3}AsO_{4} \rightleftharpoons H_{2}AsO^{-}_{4} + H^{+}](https://tex.z-dn.net/?f=H_%7B3%7DAsO_%7B4%7D%20%5Crightleftharpoons%20H_%7B2%7DAsO%5E%7B-%7D_%7B4%7D%20%2B%20H%5E%7B%2B%7D)
Hence, the expression for
is as follows.
![K_{a} = \frac{[H_{2}SO^{-}_{4}][H^{+}]}{[H_{3}AsO_{4}]}](https://tex.z-dn.net/?f=K_%7Ba%7D%20%3D%20%5Cfrac%7B%5BH_%7B2%7DSO%5E%7B-%7D_%7B4%7D%5D%5BH%5E%7B%2B%7D%5D%7D%7B%5BH_%7B3%7DAsO_%7B4%7D%5D%7D)
Let us assume that the concentration of both
and
is x.
![2.5 \times 10^{-4} = \frac{x \times x}{0.5}](https://tex.z-dn.net/?f=2.5%20%5Ctimes%2010%5E%7B-4%7D%20%3D%20%5Cfrac%7Bx%20%5Ctimes%20x%7D%7B0.5%7D)
x = 0.01118034
This means that the concentration of
is 0.01118034.
Since, we know that the relation between pH and concentration of hydrogen ions is as follows.
pH = ![-log [H^{+}]](https://tex.z-dn.net/?f=-log%20%5BH%5E%7B%2B%7D%5D)
= ![-log (0.01118034)](https://tex.z-dn.net/?f=-log%20%280.01118034%29)
= 1.958
Thus, we can conclude that the pH of a 0.500 M solution of arsenic acid is 1.958.