Answer:
His mistake was that he also gave the plants in the music room some fertilizer
Explanation:
When carrying out a reliable experiment, the only variable should be the question being tested. The question here is whether playing music for plants helps them grow faster. Therefore, all the plants should be grown in exactly the same conditions apart from the presence or absence of music.
However, Jo also added fertilizer to the plants in the room where music was playing. Therefore, we don't know whether the fertilizer or the music caused the plants to grow faster.
Instead, Jo should have not given fertilizer to any of the plants, or given fertilizer to all the plants.
solution:
the change in the boiling point is given as,
dTbp =2.30°c
elevation constant for the solvent is given by,
kb=0.512°c/m
= 4.49m
A beaker of black powder can be a mixture with different substances (i.e gunpowder: a mixture of sulfur, charcoal, etc.), an element which can probably be carbon (known as black), and a compound as well which can be potassium nitrate. Hence, the answer is D.
Answer:
There will 3.95 grams of Na2 and H2O that should be added to form a concentric required solution.
I would say C is the most correct.
In D it depends on what water source you're using. Let's say it is a waterfall, then the source of the water (melting ice or a lake) may disappear in the future.
If you're using underwater "windmills" placed in the ocean, then you would expect it to last a while as the ocean will not disappear in the near future.
