Answer:
A landform is a natural or artificial feature of the solid surface of the Earth or other planetary body.
Explanation:
For example, valleys, plateaus, mountains, plains, hills etc.
This is false, because copper is an element.
To be solution, it has to have at least 2 different substances. Solid solution of metals is often called alloy.
Answer:
c 43.38 g
Explanation:
The reaction between MnO2 and HCl can be represented by the following balanced equation:
MnO2 + HCl ---> Cl2 + MnCl2 + H2O
From the balanced equation, the theoretically required molar ratio of MnO2 to HCl is 1:1, therefore the yields would have been expected to be equal.
For the fact that HCl gives a higher yield (65.02g) than MnO2 (60.25g) according to the problem statement, HCl should be in excess, while the limiting reagent should be MnO2 .
Thus, the theoretical yield of Cl2 will be 60.25 g.
By definition, the percentage yield is given by
% Yield = (Actual Yield) / (Theoretical Yield),
This can be simplified to
Actual Yield = % Yield * Theoretical Yield
Plugging in the given values we have
Actual Yield = 72% * 60.25 = 43.38 g
<u>Answer:</u> The formation of given amount of oxygen gas results in the absorption of 713 kJ of heat.
<u>Explanation:</u>
To calculate the number of moles, we use the equation:
Given mass of oxygen gas = 83 g
Molar mass of oxygen gas = 32 g/mol
Putting values in above equation, we get:
For the given chemical equation:
<u>Sign convention of heat:</u>
When heat is absorbed, the sign of heat is taken to be positive and when heat is released, the sign of heat is taken to be negative.
By Stoichiometry of the reaction:
When 3 moles of oxygen gas is formed, the amount of heat absorbed is 824.2 kJ
So, when 2.594 moles of oxygen gas is formed, the amount of heat absorbed will be = 
Hence, the formation of given amount of oxygen gas results in the absorption of 713 kJ of heat.
Symbols on the periodic table represent an element.
Cl is also known as chlorine.
