The answer is (4), (3) is merely a change in composition, thus not chemical but physical.
Answer: (4).
Answer:
The right answer is "3 g".
Explanation:
Given:
Initial mass substance,

By using the relation between half lives and amount of substances will be:
⇒ 


Thus, the above is the correct answer.
Answer:
Fluids (air/water) either as water vapour or oxygen and carbon dioxide.
Explanation:
Heat transfer occurs through conduction, convection or radiation.
Many aties, this involves fluids whose molecules have been activated by heated by heat, moving from hotter to cooler regions, allowing for heating or cooling of the rooms.
Building materials have varying conductivity.
Answer:
First choice: 2
Explanation:
There are 2 phosphorous (P) in the substance.
Ignore the strontium (Sr3) part because you are looking to isolate the P from (PO4)2.
Break the chemical equation apart to get 1 Phosphorous atom, and 4 Oxygen atoms.
Now, multiple 1 by 2 because that are 2 phosphate to get 2 phosphorous atoms.
Answer:
B
Explanation:
Because when you go to the doctors they say, "You need to get your x-rays done" not microwave