Question One
It's more a question of unscrambling what is there. The answer is correct.
If you look at your periodic table, there is such an element as Na which I suspect might be the problem.
It has an atomic mass of 23. It's atomic number is 11 which means it is the 11th member (by mass) on the periodic table. The other 2 are oxygen and hydrogen. So Oxygen has an atomic mass of 16 and Hydrogen has an atomic mass of 1.
Oxygen is number 8 on the periodic table and hydrogen is number 1.
Molecular Mass
Na = 23
O = 16
H = 1
Total 40, just as the answer key says. I've probably given you more than you wanted to know, but if you still have trouble, leave a note.
Answer: -
12.59
Explanation: -
Strength of NaOH = 0.0179 M
Volume of NaOH = 58.0 mL = 58.0/1000 = 0.058 L
Number of moles = 0.0179 M x 0.058 L
= 1.04 x 10⁻³ mol
Mol of [OH⁻] given by NaOH = 1.04 x 10⁻³ mol
Strength of Ba(OH)₂ = 0.0294 M
Volume of Ba(OH)₂ = 60.0 mL = 60.0/1000 = 0.060 L
Number of moles = 0.0294 M x 0.060 L
= 1.76 x 10⁻³ mol
Mol of [OH⁻] given by Ba(OH)₂ =2 x 1.76 x 10⁻³ mol
Total [OH⁻] = 1.04 x 10⁻³ mol + 2 x 1.76 x 10⁻³ mol
= 4.56 x 10⁻³ mol
Total volume of the mixture = 58.0 + 60.0
= 118.0 mL
118.0 mL of the solution has 4.56 x 10⁻³ mol [OH⁻]
1000 mL of the solution has 
= 0.0386 mol
Using the relation
pOH = - log [OH-]
= - log 0.0386
= 1.41
Using the relation
pH + pOH = 14
pH = 14 - 1.41
= 12.59
Answer: 1.10x10²³ atoms of C
110202600000000000000000 atoms C
Explanation:The solution process is shown below.
0.183 mole C x 6.022x10²³ atoms C / 1 mole C
= 1.10x10²³ atoms C
or 110202600000000000000000 atoms C
Answer:
2Fe(s) + 3Cl2(g) → 2FeCl3(s)
Explanation:
Step 1: Data given
iron = Fe = solid = Fe(s)
chlorine = Cl2 = gas = Cl2(g)
iron(III) chloride = FeCl3 = solid = FeCl3(s)
Step 2: The unbalanced equation
Fe(s) + Cl2(g) → FeCl3(s)
Step 3: Balancing the equation
Fe(s) + Cl2(g) → FeCl3(s)
On the left we have 2x Cl (in Cl2) and on the right side we have 3x Cl (in FeCl3). To balance the amount of Cl we have to multiply Cl2 (on the left) by 3 and FeCl3 by 2.
Fe(s) + 3Cl2(g) → 2FeCl3(s)
On the left side we have 1x Fe and on the right side we have 2x Fe (in 2FeCl3). To balance the amount of Fe, we have to multiply Fe on the left side by 2. Now the equation is balanced.
2Fe(s) + 3Cl2(g) → 2FeCl3(s)
There doesn't seem to be a clear answer, it is placed in the center when it's substances is on the corners it doesn't give anything else
