Answer:
Explanation:The atomic number of sodium is 11. That is, the number of electrons in sodium is 11. Therefore, a sodium atom will have two electrons in the first shell, eight in the 2nd orbit, and an electron in the 3rd shell.
the branch of science that deals with the identification of the substances of which matter is composed; the investigation of their properties and the ways in which they interact, combine, and change; and the use of these processes to form new substances.the branch of science that deals with the identification of the substances of which matter is composed; the investigation of their properties and the ways in which they interact, combine, and change; and the use of these processes to form new substances.
Answer:
The answer to your question is 24.325
Explanation:
Data
Magnesium-24 Abundance = 78.70%
Magnesium-25 Abundance = 10.13%
Magnesium-26 Abundance = 11.17%
Process
1.- Convert the abundance to decimals
Magnesium-24 Abundance = 78.70/100 = 0.787
Magnesium-25 Abundance = 10.13/100 = 0.1013
Magnesium-26 Abundance = 11.17/100 = 0.1117
2.- Write an equation
Average atomic mass = (Atomic mass-1 x Abundance 1) + (Atomic mass 2 x
Abundance-2) + (Atomic mass 3 x Abundance 3)
3.- Substitution
Average atomic mass = (24 x 0.787) + (25 x 0.1013) + (26 x 0.1117)
4.- Simplification
Average atomic mass = 18.888 + 2.533 + 2.904
5.- Result
Average atomic mass = 24.325
From the given pH, we calculate the concentration of H+:
[H+] = 10^-pH = 10^-5.5
We then use the volume to solve for the number of moles of H+:
moles H+ = 10^-5.5M * 4.3x10^9 L = 13598 moles
From the balanced equation of the neutralization of hydrogen ion by limestone written as
CaCO3(s) + 2H+(aq) → Ca2+(aq) + H2CO3(aq)
we use the mole ratio of limestone CaCO3 and H+ from their coefficients, which is 1 mole of CaCO3 is to react with 2 moles of H+, to compute for the mass of the limestone:
mass CaCO3 = 13598mol H+(1mol CaCO3/2mol H+)
(100.0869g CaCO3/1mol CaCO3)(1kg/1000g)
= 680 kg
