Answer:
How do ecosystems respond to natural disasters such as fires and floods :
Explanation:
They recover in stages, gradually returning to the original system. … She plans to create various physical and biological disturbances in the ecosystem to see how populations change over time.
Answer:
19.6 g is the mass of methanol
Explanation:
Density of methanol is 0.787 g/mL.
Density means mass / volume
Methanol density = Methanol mass / Methanol volume.
Let's replace in the formula
0.787 g/mL = Methanol mass / 25 mL
0.787 g/mL . 25 mL = Methanol mass → 19.6 g
No it is not. the balanced equation is 2NH3 = N2 + 3H2
Answer is (4) - Pb.
According to the reactivity series of elements
- the elements which are above the hydrogen are more reactive than hydrogen.
- the elements which are below the hydrogen are less reactive than hydrogen.
Among the given choices, only Pb is placed above the hydrogen in the reactivity series and rest are below the hydrogen.
Hence, Pb is more active than hydrogen.
Answer:

Explanation:
First you should calculate the volume of a big sphere,so:



Then you calculate the volume of a small spehre, so:



Finally you subtract the two quantities:

