There are three different forms of potential energy. The rock hanging above the ground has a form of stored energy called gravitational potential energy. This form of energy is due to the downward pull of Earth's gravity. ... When you stretch a rubber band, the elastic potential energy of the rubber band increases.
A substance that undergoes change during a reaction, usually from coming in contact with another substance
Answer:
Forces between similar molecules are said to be <em>cohesive</em> while those between different types of molecules are said to be <em>adhesive</em>.
Water 'beads' due to its strong <em>cohesive</em> forces. The meniscus of water in a glass tube is <em>concave</em> because the <em>adhesive</em> forces are strong.
Explanation:
The water in a tube has stronger adhesive forces between the water and glass molecules, so the cohesive forces between water molecules are weaker. That makes the water 'ascend' through the tube, giving a concave form of the meniscus. Another example is mercury, which is the opposite. In this case, the cohesive forces are stronger than the adhesive ones, thus the meniscus is convex.
The chemical equation is:
CH₄ + 2O₂ → CO₂ + 2H₂O
First, we calculate the moles of methane present using:
Moles = mass / molecular mass
Moles = 20 / 16
Moles = 1.25
Next, we may observe from the chemical equation that the molar ratio between methane and oxygen is 1 : 2
So the moles of oxygen required are 2 x 1.25
2.5 moles of oxygen required
Mass = moles * molecular mass
Mass = 2.5 * 32
Moles = 80
C. 80 grams O₂
