1 mole of any substance contains Avogadro's number.
So, 1 mole of O2= 6.023x10^23 molecules
3 mole of O2= 6.023x10^23x3 molecules
= 1.8069x10^24 molecules
Each molecule of Oxygen has 2 atoms.
therefore,
1.8069x10^24 molecules= 1.8069x10^24 x 2 atoms
= 3.6138x10^24 atoms.
The mass number of this particular element is 37
An element with 17 protons will ALWAYS be chlorine.
The mass number is found by adding the element’s protons and neutrons.
protons+neutrons=mass number
Here is the math if needed,
17+20=37
Therefore the mass number is 37
I hope this helped!
Hello!
The reaction that the graph represents is
A. Exothermic because Hrxn=-167 kJTo calculate Hrxn we apply the following equation:
Looking at the graph, and at the result of the calculations, we can see that the enthalpy of the products is
lower than the enthalpy of the reagents, because the sign is negative. That means that the reaction
releases energy in the form of heat and that the reaction is
exothermic.
Have a nice day!
Answer:
One extraction: 50%
Two extractions: 75%
Three extractions: 87.5%
Four extractions: 93.75%
Explanation:
The following equation relates the fraction q of the compound left in volume V₁ of phase 1 that is extracted n times with volume V₂.
qⁿ = (V₁/(V₁ + KV₂))ⁿ
We also know that V₂ = 1/2(V₁) and K = 2, so these expressions can be substituted into the above equation:
qⁿ = (V₁/(V₁ + 2(1/2V₁))ⁿ = (V₁/(V₁ + V₁))ⁿ = (V₁/(2V₁))ⁿ = (1/2)ⁿ
When n = 1, q = 1/2, so the fraction removed from phase 1 is also 1/2, or 50%.
When n = 2, q = (1/2)² = 1/4, so the fraction removed from phase 1 is (1 - 1/4) = 3/4 or 75%.
When n = 3, q = (1/2)³ = 1/8, so the fraction removed from phase 1 is (1 - 1/8) = 7/8 or 87.5%.
When n = 4, q = (1/2)⁴ = 1/16, so the fraction removed from phase 1 is (1 - 1/16) = 15/16 or 93.75%.
Given that the volume and amount of water are kept constant,
P/T = constant
P₁/T₁ = P₂/T₂
Normal atmospheric pressure is 746 mmHg and normal boiling point of water is 100 °C.
746/100 = 589/T₂
T₂ = 79.0 °C
