<u>Answer: </u>
Phases of moon:
- New Moon
- crescent Moon
- First-quarter Moon
- gibbous Moon
- full Moon
<u>Explanation:</u>
The lunar cycle has 8 phases. The first phase is new moon. New moon is seen while the moon lies between the sun and the earth. After few days occurs the crescent moon when the moon travels towards its east. The next phase is first-quarter phase. During this phase half of the moon will be illuminated. The fourth phase is waxing gibbous moon phase where waxing refers to 'growing larger' and gibbous means 'shape' hence waxing gibbous refers to growing shape. Next is the full moon phase. This happens when the moon and the sun comes on the opposite sides of our earth. The next phase will be waning gibbous moon where the moon decreases in size. This phase is followed by third quarter and finally the waning crescent moon phase.
Density is the mass of substance per unit volume of a substance. to solve the problem, first calculate the mass of the gas.
mass gas = ( mass of balloon with gas ) - ( mass of balloon )
mass gas = 10.24 g - 2.42 g
mass gas = 7.82 g
so the density
density = m / v = 7.82 g / 5470 cm3
density = 0.00145 g / cm3
Explanation:
Activation energy, in chemistry, is the minimum amount of energy that is required to activate atoms or molecules to a condition in which they can undergo chemical transformation or physical transport. Basically, activation energy is that push that atoms need in order to undergo reactions.
All chemical reactions, including exothermic reactions, need activation energy to get started. Activation energy is needed so reactants can move together, overcome forces of repulsion, and start breaking bonds.
A catalyst lowers the activation energy of a reaction, so that a chemical reaction can take place. Increasing the temperature of a reaction has the effect of increasing the number of reactant particles that have more energy than the activation energy. Enzymes are a form of catalysts that speed up chemical reactions by lowering the activation energy.
The correct options are therefore;
- is decreased in the presence of an enzyme specific for that reaction.
- is the amount of free energy required to bring the reactants to the transition state.
- is an alternative term for the free energy of activation.
Answer:
When adding strong base to a buffer, we assume the equilibrium value of the hydroxyl ion (OH-) is zero because all hydroxyl ion (OH) react with hydrogen ion (H+) forming water. So there is no hydroxyl ion (OH-) left and values of hydroxyl ion (OH-) is become zero.
Hydrogen ion is released by weak acid which is present in the buffer solution.
