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:
B. An ionized atom has a number of protons that is unequal to the number of electrons.
Explanation:
For a neutral atom , the number of proton and electron is equal. An ionized atom has either loss or gain electron, thereby making the number of proton and electron unequal. The answer B is true because an ionized atom has either loss or gain electron to make the number of electron and proton unequal.
Option A is incorrect because a cations holds a positive charge when it loss one or more electron not when it gains one or more electron(s). Anions possess negative charge for gaining electron(s).
Option C is not true because ions can also carry negative charges and they are called anions.
Option D is false because losing one or more electron will turn an atom to a cations.
Mass = m = 40 grams
Volume = V = 9 cm³
Density = d = ?
Density is defined as the ratio of mass and volume.
So,
d = m/V
Using the values, we get
d = 40/9 = 4.44 g/cm³
This means the density of material would be 4.44 g/cm³
