Metals generally form cations, meaning they become positively charge - this positive charge is due to the loss of electrons.
Answer:
Concentration of sodium carbonate in the solution before the addition of HCl is 0.004881 mol/L.
Explanation:

Molarity of HCl solution = 0.1174 M
Volume of HCl solution = 83.15 mL = 0.08315 L
Moles of HCl = n



According to reaction , 2 moles of HCl reacts with 1 mole of sodium carbonate.
Then 0.009762 mol of HCl will recat with:

Moles of Sodium carbonate = 0.004881 mol
Volume of the sodium carbonate containing solution taken = 1L
Concentration of sodium carbonate in the solution before the addition of HCl:
![[Na_2CO_3]=\frac{0.004881 mol}{1 L}=0.004881 mol/L](https://tex.z-dn.net/?f=%5BNa_2CO_3%5D%3D%5Cfrac%7B0.004881%20mol%7D%7B1%20L%7D%3D0.004881%20mol%2FL)
Answer:
78.85
Explanation:
To <u>calculate the average atomic mass of the isotopes </u>we use the <em>given masses and abundances</em>, as follows:
- Mass of Isotope 1 * Abundance of Isotope 1 + Mass of Isotope 2 * Abundance of Isotope 2 + ....
In other words:
- 78 amu * 75/100 + 81 amu * 15/100 + 82 amu * 10/100 = 78.85
So the answer is 78.85.
Left side metals right side non metals. arrganged in groups (columns) and periods (rows), each group tells you amount of valence electrons