The percent concentration of a solution can be calculated from; mass of solute /mass of solution * 100. The mass of the solute here is 8.1 g.
<h3>What is concentration?</h3>
The term concentration refers to the amount of solute presnt in a solution. There are many ways of expressing concentration such as molarity, molality and percentage.
Here;
mass of solution = 230.5 g
Percent of solute = 3.5 %
3.5 = x/ 230.5 * 100
3.5 = 100x/230.5
230.5(3.5) = 100x
x = 230.5(3.5) /100
x = 8.1 g
Learn more about percent concentration: brainly.com/question/202460?
Answer:
1.00 × 10¹⁸
Explanation:
1. Calculate the <em>energy of one photon</em>
The formula for the energy of a photon is
<em>E</em> = <em>hc</em>/λ
<em>h</em> = 6.626 × 10⁻³⁴ J·s; <em>c</em> = 2.998 × 10⁸ m·s⁻¹
λ = 477 nm = 477 × 10⁻⁹ m Insert the values
<em>E</em> = (6.626 × 10⁻³⁴ × 2.998× 10⁸)/(477 × 10⁻⁹)
<em>E</em> = 4.165× 10⁻¹⁹ J
2. Calculate the <em>number of photons</em>
Divide the total energy by the energy of one photon.
No. of photons = 0.418 × 1/4.165 × 10⁻¹⁹
No. of photons = 1.00 × 10¹⁸
Answer:
0.607mol
Explanation:
n(AR) = mass / molar máss
= 24.3 /40
=0.607