Hydrogen-1, Carbon-13, Nitrogen-15, Fluorine-19, and Phosphorus-31 are the most useful. Out of these, Hydrogen-1 and Carbon-13 in NMR are the most useful nuclei because the these atoms are the most commonly present in organic molecules.
Answer:
The answer to your question is: number 1
Explanation:
Third law of Newton: says that for every action ,there is an equal and opposite reaction.
So, if the child is pushing an object to the right, it will recipe the same amount of force that he is exerting to the object but in opposite direction.
Number 2 and 3 are incorrect because, because the third law of Newton says "an equal and opposite reaction", not slightly more or less.
Number 4 is wrong, it is not in agreement with Newton's third law of motion.
Answer:

Explanation:
25. Boyle's Law
The temperature and amount of gas are constant, so we can use Boyle’s Law.

Data:

Calculations:

26. Ideal Gas Law
We have p, V and n, so we can use the Ideal Gas Law to calculate the volume.
pV = nRT
Data:
p = 101.3 kPa
V = 20 L
n = 5 mol
R = 8.314 kPa·L·K⁻¹mol⁻¹
Calculation:
101.3 × 20 = 5 × 8.314 × T
2026 = 41.57T

Answer:
There will be 3 peaks.
Relative height of the atomic peaks would be; 158, 160 and 162
Explanation:
We are told that Bromine has two isotopes namely 79Br and 81Br in a 1 : 1 ratio (50 : 50).
This means that a compound which contains 1 bromine atom will have two peaks in the molecular ion region but it depends on which bromine isotope is contained in the molecular ion.
Thus;
Relative height of atomic peaks is given by;
m/z = 79Br¯ 79Br+ = 158
79Br¯ 81Br+ = 160
81Br¯ 81Br+ = 162