Answer:
Chemical energy is converted into thermal and mechanical energy while kinetic energy into potential energy.
Explanation:
As the breakdown of food started, the chemical energy present in the food substances converted into thermal energy and mechanical energy. Thermal or heat energy is used to maintain the body's temperature while mechanical energy is used in other activities such as movement of muscles. Kinetic energy is also converted into potential energy when the object moves from top of a place such as hill.
Answer:
a,d,e
Explanation:
its a,d, and e because clean air keeps us alive and other organisms need it to stay alive
Answer:
Percent yield = 61.58%
Explanation:
C4H9OH + NaBr + H2SO4 --> C4H9Br + NaHSO4 + H2O
From the reaction;
1 mol of C4H9OH reacts with 1 mol of NaBr and 1 mol of H2SO4 to form 1 mol of C4H9Br
We have to obtain the limiting reagent. We do this by calculatig the mols of each reactant in the reaction;
Number of moles = Mass / Molar mass
C4H9OH; 15 / 74g/mol = 0.2027
NaBr; 22.4 / 102.89 = 0.2177
H2SO4; 32.7 / 98 = 0.3336
In this case, the limiting reagent is C4H9OH, it determines the amount of product formed.
From the stoichometry of the reaction; one mole of C4H9OH forms one mole of C4H9Br. This means 0.2027 mol of C4H9Br was formed.
Mass = Number of moles * Molar mass
Mass of C4H9Br formed = 0.2027 * 137
Mass = 27.77g
Percent yield = (Practical yield / theoretical yeield ) * 100%
Percent Yield = 17.1 / 27.77 * 100
Percent yield = 61.58%
