We know that the oxygen (O2) causes a glowing
splint to reignite, however, let us check what is missing on the products side
of the chemical equation: <span>
KBrO3 → KBr + ?
As we see, oxygen (O2) is the element missing from the other
side. Therefore the balanced chemical
equation for this decomposition is as follows: </span>
<span>2KBrO3 → 2KBr + 3O2 </span>
1) 0.89% m/v = 0.89 grams of NaCl / 100 ml of solution
=> 8.9 grams of NaCl in 1000 ml of solution = 8.9 grams of NaCl in 1 liter of solution
2) Molarity = M = number of moles of solute / liters of solution
=> calculate the number of moles of 8.9 grams of NaCl
3) molar mass of NaCl = 23.0 g /mol + 35.5 g/mol = 58.5 g / mol
4) number of moles of NaCl = mass / molar mass = 8.9 g / 58.5 g / mol = 0.152 mol
5) M = 0.152 mol NaCl / 1 liter solution = 0.152 M
Answer: 0.152 M
Answer:
Explanation: Well each branch has its own little job especially when it comes to society. First we have the Organic Chemistry Branch It includes the study of all the possible compounds which have carbon in them. Then we have the Inorganic Chemistry Branch, the inorganic compounds find their use in medicine, food, agriculture and also technology. Next we have the Biochemistry Branch it deals with chemistry happening inside the living bodies of animals and plants. This subject is huge and plays an important role in medicine, agriculture, poultry, fisheries, etc. And finally we have the Physical Chemistry Branch it deals with the physical properties of chemicals or substances. It includes topics like gaseous laws (Dalton law), thermal conduction in liquids, gases, solids. The conductivity of electrolytes (used in batteries) liquids etc. It also deals with processes like sublimation, melting point, boiling point, the crystal structure of compounds, etc.
The model would look something like the image below.
There would be a <em>central nucleus</em> containing <em>20 protons</em> and <em>20 neutrons</em>.
Surrounding the nucleus would be four concentric rings (energy levels) containing <em>20 electron</em>s.
Going out from the nucleus, the number of electrons in each ring would
be <em>2, 8, 8, 2</em>.
Answer:
<u>1. Net ionic equation:</u>
- Cl⁻(aq) + Ag⁺(aq) → AgCl(s)
<u />
<u>2. Volume of 1.0M AgNO₃</u>
Explanation:
1. Net ionic equation for the reaction of NaCl with AgNO₃.
i) Molecular equation:
It is important to show the phases:
- (aq) for ions in aqueous solution
- (s) for solid compounds or elements
- (g) for gaseous compounds or elements
- NaCl(aq) + AgNO₃(aq) → AgCl(s) + NaNO₃(aq)
ii) Dissociation reactions:
Determine the ions formed:
- NaCl(aq) → Na⁺(aq) + Cl⁻(aq)
- AgNO₃(aq) → Ag⁺(aq) + NO₃⁻(aq)
- NaNO₃(aq) → Na⁺(aq) + NO₃⁻(aq)
iii) Total ionic equation:
Substitute the aqueous compounds with the ions determined above:
- Na⁺(aq) + Cl⁻(aq) + Ag⁺(aq) + NO₃⁻(aq) → AgCl(s) + Na⁺(aq) + NO₃⁻(aq)
iv) Net ionic equation
Remove the spectator ions:
- Cl⁻(aq) + Ag⁺(aq) → AgCl(s) ← answer
2. How many mL of 1.0 M AgNO₃ will be required to precipitate 5.84 g of AgCl
i) Determine the number of moles of AgNO₃
The reaction is 1 to 1: 1 mole of AgNO₃ produces 1 mol of AgCl
The number of moles of AgCl is determined using the molar mass:
- number of moles = mass in grams / molar mass
- molar mass of AgCl = 143.32g/mol
- number of moles = 5.84g / (143.32g/mol) = 0.040748 mol
ii) Determine the volume of AgNO₃
- molarity = number of moles of solute / volume of solution in liters
- V = 0.040748mol / (1.0M) = 0.040748 liter
- V = 0.040748liter × 1,000ml / liter = 40.748 ml
Round to two significant figures: 41ml ← answer
