Answer: A) grinding coffee beans
Explanation:
A physical change is defined as a change in which there is alteration in shape, size etc. No new substance gets formed in these reactions.
A chemical change is defined as a change in which a change in chemical composition takes place. A new substance is formed in these reactions.
1. Grinding coffee : Only change in size takes place, thus a physical change
2. Baking a cake: the chemical reaction occurs by combination of flour with oxygen , thus a chemical change.
3.:converting water to hydrogen and oxygen: The decomposition iof water takes place, thus is a chemical change
4.Burning of coal: the chemical reaction occurs by combination of carbon with oxygen , thus a chemical change.
Answer:
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Answer:
1. When you first opened the bottle of coke the pressure of gas in the coke (increased) and the dissolved gas(leaves) the coke. 2. When you placed the coke in hot water , the pressure of gas in the coke (increased) and the dissolved gas(leaves) the coke 3. Therefore to increase the solubility of a gas in a liquid ( that is to make a gas more soluble in a liquid.
Explanation:
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