Answer:
We need 10.14 grams of sodium bromide to make a 0.730 M solution
Explanation:
Step 1: Data given
Molarity of the sodium bromide (NaBr) = 0.730 M
Volume of the sodium bromide solution = 135 mL = 0.135 L
Molar mass sodium bromide (NaBr) = 102.89 g/mol
Step 2: Calculate moles NaBr
Moles NaBr = Molarity NaBr * volume NaBr
Moles NaBr = 0.730 M * 0.135 L
Moles NaBr = 0.09855 moles
Step 3: Calculate mass of NaBr
Mass NaBr = 0.09855 moles * 102.89 g/mol
Mass NaBr = 10.14 grams
We need 10.14 grams of sodium bromide to make a 0.730 M solution
Answer:
4. trigonal planar symmetry.
Explanation:
The sp2 hybridization is formed with one s and two p atomic orbitals and form trigonal planar symmetry. In sp2 hybridization, there are same valence shell in both the orbitals and it gives three equivalent sp2 hybridized orbitals that are separated by 120 degrees giving trigonal planar symmetry.
Hence, the correct answer is "4. trigonal planar symmetry.".
The formation of chemical bonds occurs due to the attractive forces between oppositely charged ions (ionic bonds) or by sharing of electrons (covalent bonds).
An atom having tendency of attracting a shared pair of electrons towards itself and this chemical property is said to Electronegativity .
Thus, the attractive forces which draws in surrounding electrons for chemical bonds is electronegativity.
4 moles of NaCl is produced from 2 moles of Na₂CrO₄.
<u>Explanation:</u>
Given reaction is
PbCl₂(aq) + Na₂CrO₄(aq)→ PbCrO₄(s) + 2 NaCl (aq)
It is the balanced equation which means that on both sides of the equation, number of atoms of each element are equal.
From the above balanced equation it says that molar ratio of Na₂CrO₄ to NaCl is 1 : 2.
That is 1 mole of Na₂CrO₄ produces 2 moles of NaCl, so the molar ratio is 1:2.
2 moles of Na₂CrO₄ produces 4 moles of NaCl.
So the molar ratio of Na₂CrO₄ to NaCl is 2: 4.
