Answer:
See below
Step-by-step explanation:
(a) Shape
The formula for water is H-O-H.
The central O atom has four electron pairs around it. They try to get as far from each other as possible, so they point toward the corners of a tetrahedron.
Only two of the pairs have a hydrogen atom attached, so water has a bent shape. The H-O-H bond angle is about 104°.
(b) Chemical magnet
The O atom has a greater attraction than H for the shared electrons in the O-H bonds, so the electrons spend more time near the O.
This gives the O atom a partial negative charge (pink in the diagram) and the H atoms a partial positive charge (blue).
The water molecule acts like a chemical magnet because its negative end attracts the positive ends of other molecules, while its positive ends attract the negative ends of other molecules.
Answer:
197mL of 0,506M HCl
Explanation:
The reaction of HCl + BaCO₃ is:
BaCO₃(s) + 2HCl → BaCl₂(aq) + CO₂ + H₂O.
The moles of BaCO₃ in 9,85 g are:
9,85 g of BaCO₃ × 
= <em>0,0499 moles of BaCO₃</em>
As 1 mol of BaCO₃ reacts with two moles of HCl, for a complete reaction of BaCO₃ to dissolve this compound in water you need:
0,0499 moles of BaCO₃ × 
=<em> 0,0998 moles of HCl</em>
If you have a 0,506M HCl, you need to add:
0,0998 moles of HCl× 
= 0,197 L ≡ 197mL
I hope it helps!
Answer:
It is MgCl₂ because the total positive charge on Mg is two
Explanation:
The bond between the atoms that makes up the formula unit of the compound is an ionic bond. This bond involves the transfer of electrons between atoms.
Mg is in the second group on the period on the periodic table. It has two valence electrons and would readily lose it to have a stable atomic configuration like those of noble gases. This leaves magnesium with a net positive charge of 2. Each chlorine atom gains one electron to achieve their own octet.
Melted rock and minerals under the earths crust are called magma
