Answer:
Chemical Change
Explanation:
Physical change normally mean that the change can revert back to its orginal state, which in this case that is not possible therfore it is a chemical change.
Answer:
2.0x10¹⁷ Hz is the frequency of the X-ray
Explanation:
We can find the frequency of a wave of energy from the wavelenght and its speed using the formula:
v = λƒ
<em>Where v is speed (For electromagnetic radiation = 3.0x10⁸m/s)</em>
<em>λ is the wavelength in meters = 1.5x10⁻⁹m</em>
<em>And f is the frequency in s⁻¹ = Hz</em>
<em />
Replacing:
3.0x10⁸m/s = 1.5x10⁻⁹m*ƒ
3.0x10⁸m/s / 1.5x10⁻⁹m = f
f =
<h3>2.0x10¹⁷ Hz is the frequency of the X-ray</h3>
<em />
Answer:
the answer is 25.032g check pic for explanation
9 g of hydrogen - 42 g of nitrogen
5 g of hydrogen - x g of nitrogen

The mass of nitrogen in the second sample is 23.33 g.
<span>A solution with a pH of 4 has ten times the concentration of H</span>⁺<span> present compared to a solution with a pH of 5.
</span>pH <span>is a numeric scale for the acidity or basicity of an aqueous solution. It is the negative of the base 10 logarithm of the molar concentration of hydrogen ions.
</span>[H⁺] = 10∧-pH.
pH = 4 → [H⁺]₁ = 10⁻⁴ M = 0,0001 M.
pH = 5 → [H⁺]₂ = 10⁻⁵ M = 0,00001 M.
[H⁺]₁ / [H⁺]₂ = 0,0001 M / 0,00001 M.
[H⁺]₁ / [H⁺]₂ = 10.