Answer:
The graph represents an endothermic reaction.
The products have more energy than the reactants.
80kJ
160kJ
80kJ
160kJ
Answer:
Explanation:
13 ) symbol of enthalpy change = Δ H .
14 ) enthalpy change is nothing but heat absorbed or evolved .
During fusion enthalpy change
Δ H .= m Lf , m is mass and Ls is latent heat of fusion
During evaporation, enthalpy change
Δ H .= m Lv , m is mass and Lv is latent heat of evaporation
during temperature rise , enthalpy change
Δ H = m c Δ T
In case of gas , enthalpy change can be calculated by the following relation
Δ H = Δ E + W , Δ E is change in internal energy , W is work done by gas.
15 ) When enthalpy change is negative , that means heat is released to the environment .So reaction is called exothermic .
when heat is absorbed enthalpy change is positive . Reaction is endothermic.
Answer:
"Freezing point and ability to react with oxygen" are chemical properties
Explanation:
The change of liquid into solid is the freezing point. The melting point is more than the freezing point in certain cases of mixtures for certain organic compounds like fats. As soon as the mixture freezes it becomes solid and which results in change in the composition from the liquid and solid in this way the it drastically reduces the freezing point. The melting point gets higher due to the pressure. This happens due to the release of heat of which results in the rise of temperature to the freezing point
.Also the reaction of elements with oxygen which leads to formation of new substance is also an chemical property
Answer:
2M
Explanation:
M=mol/L
1. Find moles of CoCl2
mass of substance/molar mass = 130/129.833 = 1.001 mol
3. Substitute in molarity equation
M=(1.001/0.5)
M= around 2M
Answer:
is the limiting reagent
Explanation:
To calculate the moles :


The balanced chemical reaction is :
According to stoichiometry :
1 moles of
require = 2 moles of 
Thus 0.625 moles of
will require=
of 
Thus
is the limiting reagent as it limits the formation of product and
is the excess reagent as it is present more than the required amount.