Answer:
A. 28 years
Explanation:
Applying,
R = R'(2ᵃ/ⁿ).............. Equation 1
Where R = Original sample, R' = Sample left after decay, a = Total time taken to decay, n = half life.
From the question,
Given: R = 12 g, R' = 6 g, a = 28 years.
Substitute into equation 1 and solve for n
12 = 6(2²⁸/ⁿ)
12/6 = 2²⁸/ⁿ
2²⁸/ⁿ = 2
Equation the base,
28/n = 1
n = 28 years.
Hence the half-life is 28 years
Explanation:
so then we would know about the reproduction system and how we are born and what happens with the cells inside the womens womb and how the sperm cell meets the egg cell and creates the egg
Explanation:
1. Thermochemical equation is balance stoichiometric chemical equation written with the phases of the reactants and products in the brackets along with the enthalpy change of the reaction.
The given correct thermochemical reactions are:


2. Phase change affect the value of the enthalpy change of the thermochemical equation. This is because change in phase is accompanied by change in energy. For example:


In both reaction phase of water is changing with change in energy of enthalpy of reaction.
The shape of the H2O molecule is a Bent Triatomic.
It isn't symmetrical.
The H2O molecule is polar.
At constant temperature and pressure, increasing the amount of gas will increase the volume.