Considering that scientific notation has to move the decimal over so there is only one digit in the Tens place, that is the scientific notation.
Answer:
you can identify an unknown substance by measuring its density and comparing your results to a list of known densities. Density=mass/volume. Assume that you have to identify an unknown metal. You can determine the mass of the metal on a scale.
Answer:
Explanation:
<u>1) Data:</u>
a) Hypochlorous acid = HClO
b) [HClO} = 0.015
c) pH = 4.64
d) pKa = ?
<u>2) Strategy:</u>
With the pH calculate [H₃O⁺], then use the equilibrium equation to calculate the equilibrium constant, Ka, and finally calculate pKa from the definition.
<u>3) Solution:</u>
a) pH
b) Equilibrium equation: HClO (aq) ⇄ ClO⁻ (aq) + H₃O⁺ (aq)
c) Equilibrium constant: Ka = [ClO⁻] [H₃O⁺] / [HClO]
d) From the stoichiometry: [CLO⁻] = [H₃O⁺] = 2.29 × 10 ⁻⁵ M
e) By substitution: Ka = (2.29 × 10 ⁻⁵ M)² / 0.015M = 3.50 × 10⁻⁸ M
f) By definition: pKa = - log Ka = - log (3.50 × 10 ⁻⁸) = 7.46
Given , Speed of light = 3 × 10⁸ m/s
Distance = 40 × 1.61× 1000 m
= 264400 m
We know that, speed = distance/time
so, time = distance/speed
t = 264400 / 3 × 10⁸
t = 0.00881333 sec Approx
The answer is 0.00881333 sec Approx