Answer:
The same number of each element present before the reaction takes place must also be present on the product side of the equation. Coefficients are placed in front of a chemical formula to show the number of moles of that substances that are necessary for the reaction to occur.
Explanation:
If you are referring to to the molecule, CO, it contains two atoms , C1+O1
Answer:
There are 0.5 mole in 20g of argon.
Explanation:
40 g of argon = 1mole
Then 20g of argon is,
→ 1/40 × 20
→ 0.5 mole
Answer: True.
Explanation.
The group 7A is actually named group 17.
That group is the halogens: F, Cl, Br, I, At, and Ts (Ts is one of the last elements discovered).
Those elements have 7 valence electrons (notice that it is the same number as the second digit in 17).
The atoms with 7 valence electrons will "easily" gain one electron to get the configuration of the next noble gas (8 valence electrons). That is why these elements gain electrons to form ions.
When atoms gain electrons form anions (negative ions). For example: F(-), Cl(-), Br(-), I(-).
