valence electrons are the number of electrons in the outer shell. there can only be 8 electrons in the outer shell. The number of valence electrons can be used to determine how many bonds are needed.
For example: H2O
O (oxygen) has 6 valence electrons
H (hydrogen) has 1 valence electron
O needs 2 more electrons to be stable
H needs 1 more electron to be stable
O forms one bond with two H atoms to form H2O.
4. A
because PbCl2 is an ionic compound and it's solid, so it's a substance.
It cannot be mixture, because it's a pure molecule.
5. D
despite that both substances are gases, colorless they are different molecules, so they should have different either chemical and physical properties
6. C
this substance made from W atoms and others are made from molecules
Nickle (II) sulfite - b/c the charge on Ni can be +2 or +3 i Believe. SO3 has a charge of -2 the you need nickel II (+2) to make a proper ionic bond
Answer: baking soda + vinegar → carbon dioxide + water + sodium acetate
First you just have to say hi then when the other person says hi you just talk abt something you both wanna talk abt
