Answer:
The first two options are correct
Explanation:
The first two options are part of the benefits of a parallel connection of bulbs in a circuit. Here, the voltage of each connecting bulb is the same as the voltage of the bulb in the circuit hence all the bulbs have the same voltage running through them. Thus, when one bulb is removed/burns out, it does not affect the remaining bulbs (those ones will remain lit). Also, the addition of bulb(s) does not cause the remaining bulbs in the circuit to get dimmer (since they will all have the same voltage).
Nitrous acid<span> dissociates as follows:
</span>
HNO₂(s) ⇄ H⁺(aq) + NO₂⁻(aq)
According to the equation, an acid constant has the following form:
Ka = [H⁺] × [NO₂⁻ ] / [HNO₂]
From pH, we can calculate the concentration of H⁺ and NO₂⁻:
[H⁺] = 10^-pH = 10^-2.63 = 0.00234 M = [NO₂⁻]
Now, the acid constant can be calculated:
Ka = 0.00234 x 0.00234 / 0.015 = 3.66 x 10⁻⁴
And finally,
pKa = -log Ka = 3.44
Answer:
1.2x10⁻⁵M = Concentration of the product released
Explanation:
Lambert-Beer's law states the absorbance of a solution is directly proportional to its concentration. The equation is:
A = E*b*C
<em>Where A is the absotbance of the solution: 0.216</em>
<em>E is the extinction coefficient = 18000M⁻¹cm⁻¹</em>
<em>b is patelength = 1cm</em>
<em>C is concentration of the solution</em>
<em />
Replacing:
0.216 = 18000M⁻¹cm⁻¹*1cm*C
<h3>1.2x10⁻⁵M = Concentration of the product released</h3>
To measure length scientists may use rulers, meter sticks, etc. and to measure mass they may use a balance.