Answer:
Copper is a metal made up of copper atoms closely packed together. As a result, the electrons can move freely through the metal. For this reason, they are known as free electrons. They are also known as conduction electrons because they help copper be a good conductor of heat and electricity.
Explanation:
Answer:
The electron stays in an excited state for a short time. When the electron transits from an excited state to its lower energy state, it will gice off the same amound of energy needed to raise to that level. This emitted energy is a photon.
Answer:
Mass of compound c = 6 g
Explanation:
Given:
Mass of compound a = 2.5 g
Mass of compound b = 3.5 g
Find:
Mass of compound c
Computation:
According to Law of conservation of mass
Mass of compound a + Mass of compound b = Mass of compound c
Mass of compound c = 2.5 + 3.5
Mass of compound c = 6 g
Answer:
c. 0.2 M HNO₃ and 0.4 M NaF
.
Explanation:
A buffer is defined as the mixture of a weak acid with its conjugate base or a weak base with its conjugate acid.
A weak acid or weak base are defined as an acid or base that partially dissociates in aqueous solution. in contrast, a strong acid or base are acids or bases that is dissociated completely in water.
Thus:
a. 0,2M HNO₃ and 0.4 M NaNO₃. This is a mixture of a strong acid with its conjugate base. <em>IS NOT </em>a buffer.
b. 0.2 M HNO₃ and 0.4 M HF
. This is a mixture of two strong acids. <em>IS NOT </em>a buffer.
c. 0.2 M HNO₃ and 0.4 M NaF
. NaF is the conjugate base of a weak acid as HF is.
The reaction of HNO₃ with NaF is:
HNO₃ + NaF → HF + NaNO₃
That means that in solution you will have a weak acid (HF) with its conjugate base (NaF). Thus, this mixture <em>IS </em>a buffer.
d. 0.2 M HNO₃ and 0.4 M NaOH. This is the mixture of a strong acid with a strong base, thus, this <em>IS NOT </em>a buffer.
I hope it helps!