In a solution of KBr and water; KBr is the solute and water is the solvent;
Therefore; to achieve 3% by mass; it means we are going to have 3% of the mass being the solute and the other 97 % being the solvent.
Thus; KBr (solute) = 3/100 × 300 (total mass) = 9 g
Hence; the appropriate masses will be; 9.00 g of KBr and 291 g of water.
Answer: The concentration of
ions in vinegar is 0.001 M.
Explanation:
Given: pH = 3.0
pH is the negative logarithm of concentration of hydrogen ion.
The expression for pH is as follows.
![pH = - log [H^{+}]](https://tex.z-dn.net/?f=pH%20%3D%20-%20log%20%5BH%5E%7B%2B%7D%5D)
Substitute the value into above expression as follows.
![pH = - log [H^{+}]\\3.0 = - log [H^{+}]\\conc. of H^{+} = antilog (- 3.0)\\= 0.001 M](https://tex.z-dn.net/?f=pH%20%3D%20-%20log%20%5BH%5E%7B%2B%7D%5D%5C%5C3.0%20%3D%20-%20log%20%5BH%5E%7B%2B%7D%5D%5C%5Cconc.%20of%20H%5E%7B%2B%7D%20%3D%20antilog%20%28-%203.0%29%5C%5C%3D%200.001%20M)
Thus, we can conclude that the concentration of
ions in vinegar is 0.001 M.
Answer:

Explanation:
Hello,
In this case, since a change in science is widely known to be considered as a subtraction between the the final and initial values of two measured variables and is represented via Δ, here the final density is 5.43 g/mL and the initial one was 3.21 g/mL, therefore, the change in density is:

Best regards.
Answer:
144g of H₂O
Explanation:
3NH₄ClO₄(s) + 3Al → Al₂O₃(s) + AlCl₃(s) + 3NO(g) + 6H₂O(g)
From the equation:
3 moles of NH₄ClO₄ produced 6 moles of H₂O
4 moles of NH₄ClO₄ produced ? moles of H₂O
(4 ₓ 6)/3 =
= 8 moles of H₂O
1 mole of H₂O = (1 × 2) + 16 = 18g (The Relative Molecular mass of H₂O)
8 moles of H₂O = ?
Therefore 8 × 18 = 144g
=144g of H₂O
Answer:
the mass of 2.9 moles of calcium is 116 g
Explanation:
The computation of the mass of 2.9 moles of calcium is shown below
As we know that
Mole = mass ÷ molar mass
where,
Moles be 2.9
And, we know that the molar mass of calcium be 40g/mol
Now put the values to the above formula
2.9 = Mass ÷ 40
So, the mass would be
= 40 × 2.9
= 116 g
Hence, the mass of 2.9 moles of calcium is 116 g