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.
False beacause that was one of the first things they thought
Potassium is placed where it is based on its properties and it's reactivity. It's also placed there based on it's atomic number.
This may help you
<span>You need to use some stoichiometry here. The only way to do that is if you're working in moles. Since you're given grams of Al, you can convert that moles by dividing by the molar mass.
Then from looking at the coefficients in your equation, you can see that for however many moles of Al react, the same numbers of moles of Fe will be produced, but only half as many moles of Al2O3 will be produced.
To go back to grams, multiply the moles of each product that you get by their molar masses!</span>
Answer:
It corresponds to Charles' Law
Explanation:
Charles's Law corresponds to one of the gas laws, where temperature and volume are related, to constant pressure. That is, according to said equation, the volume of a gas varies directly with the temperature, under conditions of constant pressure.
