Buffer is a solution which resist the change in pH with addition of small amount of acid or base.
Hence when small amount of acid is added to buffer its pH will not change, as the buffer has the capacity to resist the change in pH on small addition of acid or base to it.
Buffer is mixture of weak acid/base and its conjugate base/acid.
Hence when small amount of acid is added to HA/A-. The H+ ions added reacts with the conjugate base A- in buffer forming the weak acid and thus keeping the pH same.
I'm quite sure it's activity level. One other thing that could've been said is metabolism, but that isn't there. However, food is consumed for the body to have energy, and without that energy we wouldn't be able to function. And when we let that intake of food settle, it's stored as fat. But because of activity level, we are capable of burning those calories.
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Answers:
Most of the world’s energy comes from what three sources?
Oil, coal, and gas.
These energy sources are called <u>fossil</u> fuels and they are <u>non-renewable</u> resources.
Fuel type: oil
How it's formed: from the remains of ancient marine organisms
Its uses: transportation, industrial power, heating and lighting, lubricants, petrochemical industry, and use of by-products
Fule type: coal
How it's formed: when dead plant matter decays into peat and is converted into coal by the heat and pressure of deep burial
Its uses: electricity generation, metal production, cement production, chemical production, gasification, and other industrial uses
Fuel type: gas
How it's formed: decomposed organic matter mixed with mud, silt, and sand on the seafloor
Its uses: heating & cooling buildings, cooking foods, fueling vehicles, and electricity generation