The answer is the 3rd choice
Answer: Heat causes surrounding air to rapidly expand and vibrate, which creates the pealing thunder we hear a short time after seeing a lightning flash.
Answer:
The correct answer is 40.7 grams.
Explanation:
Based on the given information, the volume of copper sulfate added to the solution is 255 ml or 0.255 L. The molarity of copper sulfate is not given, so let us consider it to be 1 M, which can also be written as 1 moles per liter.
The moles of copper sulfate can be determined by using the formula,
Moles = Molarity * Volume in Liters
Moles of CuSO4 = 1 moles/Liter * 0.255 L
Moles of CuSO4 = 0.255 moles
The mass of CuSO4 added in the solution will be,
Mass of CuSO4 = Moles * Molecular mass
= 0.255 moles * 159.609 grams per mole
= 40.7 grams.
The six electrons in the outermost shell allow selenium to have a variety of valence numbers.
The valence of selenium depends on which compound it is in. Selenium is very similar to sulfur. It may have a valence of 6.
EXAMPLE:
selenium hexafluoride SeF6, selenium trioxide SeO3
May have 4;
example
selenium tetrafluoride SeF4, selenium dioxide SeO2
MAy have 2;
example
selenium difluoride SeF2, selenium dichloride SeCl2
and may have -2;
example
hydrogen selenide H2Se
Answer:
9.52g of N2
Explanation:
The equation of the reaction is given as;
2NO(g) + 2H2(g) → N2(g) + 2H2O(l)
From the stochiometry of the reaction;
2 mol : 2 mol : 1 mol : 2 mol
60g : 4g : 28g :
(
Mass = Number of moles * Molar mass)
Converting the masses given to moles;
Number of moles of NO = mass / molar mass = 20.4 / 30 = 0.68
Number of moles of H2 = mass / molar mass = 5.10 / 2 = 2.55
In this reaction, the limiting reactant is NO
60g of NO produces 28g of N2,
20.4g of NO would produce xg of N2
60 = 28
20.4 = X
X = (20.4 * 28) / 60
X = 9.52g
