Lithium, Sodium, Potassium; any of the Alkali Metals, which are farthest left on the periodic table. This is because they only have one electron in their outermost shell, so they would rather lose an electron rather than try to gain 7 to achieve that full outer shell.
Answer:
0.71
Explanation:
The molecular mass of NaCl is, 23+35.5
= 58.5
1 mole means molecular mass (in gram)
In 58.5 gm NaCl there is 1 mole.
So, 42.1 gm NaCl contains 42.1/58.5 =0.71 moles.
Answer:
Molarity = 0.95 mol/dm³
Explanation:
Given data:
Volume of H₂SO₄ = 15.8 cm³
Volume of NaOH = 20 cm³
Concentration of NaOH = 1.5 mol/dm³
Concentration of H₂SO₄ = ?
Solution:
Chemical equation:
NaOH + H₂SO₄ → Na₂SO₄ + H₂O
First of all we will calculate the number of moles of NaOH and for that we will convert the units first,
Volume = 20 cm³/1000 = 0.02 L
Concentration of NaOH = 1.5 mol/dm³
1 mol/dm³ = 1 mol/L
Concentration of NaOH = 1.5 mol/L
Number of moles of NaOH:
Molarity = number of moles / volume in L
1.5 M = number of moles / 0.02 L
Number of moles = 1.5 M ×0.02 L
Number of moles = 0.03 mol
Now we will compare the moles of NaOH and H₂SO₄
NaOH : H₂SO₄
2 : 1
0.03 : 1/2×0.03 = 0.015 mol
Concentration of H₂SO₄:
Volume of H₂SO₄:
15.8 cm³/1000 = 0.0158 L
Molarity = number of moles / volume in L
Molarity = 0.015 mol / 0.0158 L
Molarity = 0.95 mol/L
1 mol/L = 1 mol/dm³
Molarity = 0.95 mol/dm³
Answer:
decimal and unit ex 1.5 inches
