Answer is: the amu of a sodium atom is 23.
The unified atomic mass unit (amu) is a standard unit of atom mass.
One unified atomic mass unit is approximately the mass of one nucleon (proton or neutron).
The unified atomic mass unit is equal 1.66·10⁻²⁷ kg.
n(p⁺) = 11; number of protons in sodium atom.
n(n°) = 12; number of neutrons of sodium atom.
n(p⁺ + n°) = 11 + 12.
n(p⁺ + n°) = 23; number of nucleons in sodium atom.
A. How religion and philosophy different
All the other choices (b-d) can be explained by science while a can be explain by history I think
Answer:

Explanation:
Hello,
In this case, since the undergoing chemical reaction is:

The corresponding moles of carbon dioxide occupying 40.0 mL (0.0400 L) are computed by using the ideal gas equation at 273.15 K and 1.00 atm (STP) as follows:

Then, since the mole ratio between carbon dioxide and calcium carbonate is 1:1 and the molar mass of the reactant is 100 g/mol, the mass that yields such volume turns out:

Regards.
Answer:
V = 42.6 L
Explanation:
Given data:
Number of moles of Cl₂ = 1.9 mol
Temperature and pressure = standard
Volume occupy = ?
Solution:
The given problem will be solve by using general gas equation,
PV = nRT
P= Pressure
V = volume
n = number of moles
R = general gas constant = 0.0821 atm.L/ mol.K
T = temperature in kelvin
By putting values,
1 atm × V = 1.9 mol ×0.0821 atm.L /mol.K × 273.15 k
V = 42.6 atm.L / 1 atm
V = 42.6 L
I hope this picture helps