Answer:
3%
Explanation:
Substract the actual error from the final and multiply by 100
Halogens
Explanation:
Halogens are a group of non-metals located in the seventh group on the periodic table. The will only gain one electron during a chemical reaction.
- Halogens have a seven electrons in their outermost shell.
- To complete the number of electrons in this shell, they need to gain an additional electron.
- One more electron makes the halogen similar to the corresponding noble gas which is very stable.
- Halogens are very reactive groups of elements and are highly electronegative.
- They have a high affinity for electrons.
- These elements are fluorine, chlorine, bromine, iodine and Astatine.
learn more:
Halogens brainly.com/question/6324347
#learnwithBrainly
Answer:
No
Explanation:
The same amount of matter is present before and after chemical and physical changes. Matter cannot be created or destroyed
A computer screen is energy transfer