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:
percentage dissociation of trimethylacetic acid in a 0.57M aqueous solution = 0.40%
Explanation:
check attachment below for more information o the answer.
Explanation:
It is given that, the Average Speed of the orbiting space shuttle is 17500 miles/hour.
We need to convert the speed in kilometers/
second
We know that,
1 mile = 1.609 km
or
1 km = 0.621 miles
1 hour = 3600 seconds
Now cancel the miles in numerator.
So, 17500 miles/hour is equal to 7.82 km/s.
Answer:
renewable energy sources such as solar and wind DONT emit carbon dioxide and other greenhouse gases that contribute to global warming
Explanation:
