"One possibility is that the battle between the virus and your immune system can take as long as two weeks.
It could be the immune system holds the virus at bay,” said Tompkins.
Or, your immune system has to work so hard that after two weeks it’s inflamed and that’s what makes you feel bad.
Once a chemical bond is formed, the atoms are rearranged to form a stronger bond, affecting the hardness, malleability, etc. The stronger the bond, the easier a substance will break, or, if its a liquid, it will resist seperation.
Answer: Some signs of a chemical change are a change in color and the formation of bubbles. The five conditions of chemical change: color chage, formation of a precipitate, formation of a gas, odor change, temperature change.
11. D
12.C
13. For 13 i would say B but not so sure
14. A
Answer:
d. compound
Explanation:
compound and elements are pure substances