Scientists use special tools to do their work. They gather data, or information, as they seek to learn about the world. In order to solve problems they must record data that is accurate and organized. This is an important part of the scientific method.
Time taken for star to reach Earth = 7.5 years
<h3>Further explanation</h3>
Given
7.5 light years(distance Earth-star)
Required
Time taken
Solution
Speed of light=v = 3 x 10⁸ m/s
1 light years = 9.461 × 10¹⁵ m= distance(d)
So time taken for 1 light years :
time(t) = distance(d) : speed(v)
t = 9.461 × 10¹⁵ m : 3 x 10⁸ m/s
t = 3.154 x 10⁷ s = 1 years
So for 7.5 light years, time taken = 7.5 years
POH value was calculated by the negative logarithm of hydroxide ion concentration.
To know the hydrogen ion concentration, we need to know the pH value, that can be found out if pOH is known
pH + pOH = 14
pH = 14 - pOH
pH = 10.65
once the pH is known we have to find the antilog.
[H⁺] = antilog (-pH)
antilog can be found by
[H⁺] = 10^(-10.65)
[H⁺] = 2.2 x 10⁻¹¹ M
Potassium is placed where it is based on its properties and it's reactivity. It's also placed there based on it's atomic number.