A 72 kg athlete climbs a rope to a height of 12m. Calculate the increase in gravitational potential energy it has experienced.
Answer:
8467.2J
Explanation:
Given parameters:
Mass of the athlete = 72kg
Height of the climb = 12m
Unknown:
Increase in gravitational potential energy it has experienced = ?
Solution:
Gravitational potential energy is the energy due to the position of a body. It is mathematically expressed as;
Gravitational potential energy = m x g x h
m is the mass
g is the acceleration due to gravity = 9.8m/s²
h is the height
Insert the parameters and solve;
Gravitational potential energy = 72 x 9.8 x 12
GPE = 8467.2J
Answer:
The balanced chemical equation: NH₃ + 2 HF → NH₄⁺ + HF₂⁻
Explanation:
According to the Brønsted–Lowry acid–base theory, the acid- base reaction is a type of chemical reaction between the acid and base to give a conjugate acid and a conjugate base.
In this reaction, a Brønsted–Lowry acid loses a proton to form a conjugate base. Whereas, a Brønsted–Lowry base accepts a proton to form a conjugate acid.
Acid + Base ⇌ Conjugate Base + Conjugate Acid
The acid dissociation constant (Kₐ) <em>signifies the acidic strength of a chemical species.</em>
∵ pKₐ = - log Kₐ
Thus for a strong acid, Kₐ value is large and pKₐ value is small.
pKₐ (HF) = 3.2 → strong acid
pKₐ (NH₃) = 38 → weak acid
<u>The chemical reaction involved in the dissolution process:</u>
NH₃ + 2 HF → NH₄⁺ + HF₂⁻
In this acid-base reaction, the acid HF reacts with NH₃ base to give the conjugate base HF₂⁻ and conjugate acid NH₄⁺.
<u>HF (acid) donates a proton to form the conjugate base, HF₂⁻ ion. NH₃ (base) accepts a proton to form the conjugate acid. </u>
HNO2 is the formula for Nitrous Acid
The correct answer is slow