Answer:
The correct answer is - Frequency is the number of wavelengths, which is measured in hertz.
Explanation:
Frequency is the number of waves that go through a fixed point at a particular time. Hertz is the SI unit for frequency which means that one hertz is equal to a unit number of waver passes in a unit time to a fixed point.
As the frequency of a wave increases which means the number of waves increases in the unit time, the shorter the wavelength will be.
a higher frequency wave has more energy than a lower frequency wave with the same amplitude.
Answer:
Ca(OH)₂ (aq) + 2NH₄Cl (aq) → CaCl₂ (aq) + 2NH₃ (g) + 2H₂O (l)
Ca²⁺ + 2OH⁻ + 2NH₄⁺ + 2Cl⁻ → Ca⁺² + 2Cl⁻ + 2NH₃ (g) + 2H₂O (l)
2OH⁻ + 2NH₄⁺ → 2NH₃ (g) + 2H₂O (l)
Answer:
She should not have multiplied the nitrogen atom by subscript 2.
Explanation:
Chemical formula:
3(NH₄)₂SO₄
Elements present in given formula:
Nitrogen
Hydrogen
Sulfur
Oxygen
Total number of atoms of elements:
N = 3×1×2 = 6
H = 4×2×3 = 24
S = 1×3 = 3
O = 3×4 = 12
The number nitrogen atoms are six. Elena did mistake by counting the number of nitrogen. She should didn't multiplied the nitrogen atom by subscript 2.
Atoms<span> are </span>arranged in molecular compounds in groups.
<span>
For </span>covalent compounds<span>: </span>
<span>consider drawing the lewis structure of the covalent compound in question, putting the atom which is least electronegative (save hydrogen) in the center.
</span>
Answer : The expected coordination number of NaBr is, 6.
Explanation :
Cation-anion radius ratio : It is defined as the ratio of the ionic radius of the cation to the ionic radius of the anion in a cation-anion compound.
This is represented by,

When the radius ratio is greater than 0.155, then the compound will be stable.
Now we have to determine the radius ration for NaBr.
Given:
Radius of cation,
= 102 pm
Radius of cation,
= 196 pm

As per question, the radius of cation-anion ratio is between 0.414-0.732. So, the coordination number of NaBr will be, 6.
The relation between radius ratio and coordination number are shown below.
Therefore, the expected coordination number of NaBr is, 6.