Terms in this set (28) Explain how knowledge of chemistry can be a more informed citizens? Knowledge of chemistry and other sciences can help you evaluate the data presented, arrive at an informed opinion, and take appropriate action.
Answer:
Properties of metals, worksheet 6.1
Explanation:
100.133 degree celsius is the boiling point of the solution formed when 15.2 grams of CaCl2 dissolves in 57.0 g of water.
Explanation:
Balanced eaquation for the reaction
CaCl2 + 2H20 ⇒ Ca(OH)2 + HCl
given:
mass of CaCl2 = 15.2 grams
mass of the solution = 57 grams
Kb (molal elevation constant) = 0.512 c/m
i = vont hoff factor is 1 as 1 mole of the substance is given as product.
Molality is calculated as:
molality = 
= 
= 0.26 M
Boiling point is calculated as:
ΔT = i x Kb x M
= 1 x 0.512 x 0.26
= 0.133 degrees
The boiling point of the solution will be:
100 degrees + 0.133 degrees (100 degrees is the boiling point of water)
= 100.133 degree celcius is the boiling point of mixture formed.
The chemical equation would be:
2NO(g) + O2(g) --> 2NO2 (g)
<span>At equilibrium state, the partial pressure of the gases would be as follows : </span>
<span>NO = 522 - 2x </span>
<span>O2 = 421 - x </span>
<span>NO2 = 2x </span>
<span>- - - - - - - - - - - - -</span>
<span>943 - x = 748 </span>
<span>x = 195</span>
Calculating for Kp,
<span>Kp = (NO2)^2/ ((NO)^2 * (O2)) </span>
<span>Kp = (2 * 195)^2/ ((522 - 2 * 195)^2 * (421 - 195)) </span>
<span>Kp = 0.0386 </span>
The most abundant element in the Sun and in the stars are hydrogen and helium. Like most of the stars, there is a spontaneous radioactive reaction happening in the Sun. Hydrogen is transformed into Helium. As long as the stars are young, the most abundant element is hydrogen.
