Answer:
1.3223 acres
Explanation:
a football field's area is 360 feet (120 yards) x 160 feet (53.333 yards) = 57,600 sq. feet
if the area of an acre is 43,560 sq. feet, then a football field in acres = 57,600 sq. feet / 43,560 sq. feet = 1.3223 acres
we can verify our answer by doing the same calculation in sq. yards:
football field = 120 yards x 53.33 yards = 6,400 sq. yards
an acre is 4,840 sq. yards
football field in acres = 6,400 sq. yards / 4,840 sq. yards = 1.3223 acres
<em><u>examples of metalloids :
</u>Boron,Silicon ,Germanium are some metalloids ...
<u>what they do:
</u>they are used to form the semiconductors and these semiconductors are used in modern computer technology like in circuits ,chips and computer based gadgets... :) <u>
</u></em>
Answer:
It converts energy in food into a more usable form. (Cellular Respiration-The enzyme-controlled process in which energy is released from food and converted into a form that the cell can use.)
Explanation:
Answer:
C(graphite) → C(diamond), ΔH = - 0.45 kcal
CH4 + 2O2 → CO2 + 2H2O + 212,800 cal
Explanation:
C(graphite) → C(diamond), ΔH = - 0.45 kcal
CH4 + 2O2 → CO2 + 2H2O + 212,800 cal
These reactions are exothermic reaction because heat is evolved.
The energy changes occur during the bonds formation and bonds breaking.
There are two types of reaction endothermic and exothermic reaction.
Endothermic reactions:
The type of reactions in which energy is absorbed are called endothermic reactions.
In this type of reaction energy needed to break the bond are higher than the energy released during bond formation.
For example:
C + H₂O → CO + H₂
ΔH = +131 kj/mol
it can be written as,
C + H₂O + 131 kj/mol → CO + H₂
Exothermic reaction:
The type of reactions in which energy is released are called exothermic reactions.
In this type of reaction energy needed to break the bonds are less than the energy released during the bond formation.
For example:
Chemical equation:
C + O₂ → CO₂
ΔH = -393 Kj/mol
it can be written as,
C + O₂ → CO₂ + 393 Kj/mol
Because copper sulphate is not an ionic substance, no bonds are changed when it is dissolved. Thus it has to be a physical change
