Answer:
272
Explanation:
hope it helps i double checked the math :D
Answer:
178.98 sq. feet
Explanation:
The path and the garden has been shown in the figure below. The green area is the garden and the area in brown is the path.
It has been given that,
Radius of garden = 8 feet
So, the area of garden = 3.14 × 8 × 8 = 200.96 sq. feet
The total radius of the land including garden and path = 8 + 3 = 11 feet
So, the total are of land including garden and path = 3.14 × 11 × 11 = 379.94 sq. feet
So, the area of path = Total area of the land - area of garden
Area of path = 379.94 - 200.96 = 178.98 sq. feet
Answer:
Explanation:
a) In an exothermic reaction, the energy transferred to the surroundings from forming new bonds is ___more____ than the energy needed to break existing bonds.
b) In an endothermic reaction, the energy transferred to the surroundings from forming new bonds is ___less____ than the energy needed to break existing bonds.
c) The energy change of an exothermic reaction has a _____negative_______ sign.
d) The energy change of an endothermic reaction has a ____positive________ sign.
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
Answer:
a. slows diffusion
Explanation:
Gas exchange on respiratory surfaces in the body (the lungs) occurs through a process known as diffusion. Blood which is low in oxygen and high in carbondioxide (carried from cells) goes through an exchange in the lung's alveoli (where oxygen concentration is high and carbondioxide is low). The oxygen in the alveoli diffuses into the blood, while the carbondioxide in the blood diffuses into the alveoli. This diffusion is possible because of the concentration gradient across the membranes.
Pneumonia is the inflammation of the lungs due to injury or infection. Liquid (pus) accumulates in the alveoli (a natural immune response to the infection or injury), a condition known as pulmonary edema which makes it harder for gases to be exchanged between the blood and the alveoli, thereby making breathing difficult. This slows down diffusion and if the condition is severe enough, can cause a respiratory failure where oxygen levels in the blood are critically low and carbondioxide levels are very high.
1.hydrogen
2.carbon
3.argon
4.titanium
5.cesium