Answer:
Below are some patterns in the charge for elements in each group.
Group 1 elements : 1 valence electron and form ions with charge +1
Group 2 elements : 2 valence electrons and form ions with charge + 2
Group 3 elements : 3 valence electrons and form ions with charge + 3(there are some exceptions as well)
Elements in groups 4 and 5 are unpredictable also the D block elements consist of multiple oxidation states..
Group 6 elements : 6 valence electrons, form ions with charge -2
Group 7 elements: 7 valence electrons, form ions with charge -1
The octet rule is being followed, the elements form either ionic bond or covalent bond to fulfill it.
eg: when a K atom forms a K+ ion, the ion has the same electron configuration as the noble gas Ar (argon).
When an O atom gains 2 electrons to form the O²⁻ ion, the ion has the same electron configuration as the noble gas Ne (neon).
Note: Boron (B) is in Group 3 but doesn't form ions.
The thing that two changes have in common that snails growing shells and rust forming on a bicycle frame is option D. Both are caused by cooling.
<h3>How come snails develop shells?</h3>
Calcium carbonate is said to be the material that makes up the shell. The snail's shell expands as it grows to accommodate its growing body. Snails and slugs are also members of the mollusc family of creatures.
Therefore, note that air that has been mixed with the metal can make rust to develop. and as such, option D. Both are caused by cooling. is correct.
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See full question below
What do these two changes have in common? snails growing shells rust forming on a bicycle frame Select all that apply.
A. Both are only physical changes.
B. Both are caused by heating.
C. Both are chemical changes.
D. Both are caused by cooling
I would say C bc I don’t rlly think it’s A or B
The answer is the reaction ins a cold pack
Because medications contains chemicals, it would dissolve into the water and not only would it pollute the water, it could flow out into areas where people are exposed to these waters.