Answer:
1.0 × 10⁻⁹ M.
Explanation:
<em>∵ [H₃O⁺][OH⁻] = 10⁻¹⁴.</em>
[H₃O⁺] = 1.0 x 10⁻⁵ M.
<em>∴ [OH⁻] = 10⁻¹⁴/[H₃O⁺]</em> = 10⁻¹⁴/(1.0 x 10⁻⁵ M) = <em>1.0 × 10⁻⁹ M.</em>
Answer: 7
Explanation:
Before a number but after a decimal. The zeros at the end would usually mean that it doesn't count but since the numbers are before the zeros and after a decimal it's 7 sig figs
The energy increases because the molecules in water move faster
The frequency : a) 7.5 x 10¹⁴ /s
<h3>Further explanation</h3>
Radiation energy is absorbed by photons
The energy in one photon can be formulated as

Where
h = Planck's constant (6,626.10⁻³⁴ Js)
f = Frequency of electromagnetic waves (/s or Hz)
f = c / λ
c = speed of light
= 3.10⁸ m/s
λ = wavelength
The wavelength(λ) of purple light is 400 x 10⁻⁹ m, so the frequency :
