1.66 M is the concentration of the chemist's working solution.
What is molarity?Molarity (M) is the amount of a substance in a certain volume of solution. Molarity is defined as the moles of a solute per litres of a solution. Molarity is also known as the molar concentration of a solution.
In this case, we have a solution of Zn(NO₃)₂.
The chemist wants to prepare a dilute solution of this reactant.
The stock solution of the nitrate has a concentration of 4.93 M, and he wants to prepare 620 mL of a more dilute concentration of the same solution. He adds 210 mL of the stock and completes it with water until it reaches 620 mL.
We want to know the concentration of this diluted solution.
As we are working with the same solution, we can assume that the moles of the stock solution will be conserved in the diluted solution so:
[tex]n_1[/tex]= [tex]n_2[/tex] (1)
and we also know that:
n = M x [tex]V_2[/tex]
If we replace this expression in (1) we have:
[tex]M_1[/tex] x [tex]V_1[/tex]= [tex]M_2[/tex] x [tex]V_2[/tex]
Where 1, would be the stock solution and 2, the solution we want to prepare.
So, we already know the concentration and volume used of the stock solution and the desired volume of the diluted one, therefore, all we have to do is replace the given data in (2) and solve for the concentration which is [tex]M_2[/tex]:
4.93 x 210 = 620 x[tex]M_2[/tex]
[tex]M_2[/tex] = 1.66 M
This is the concentration of the solution prepared.
Learn more about molarity here:
https://brainly.com/question/19517011
#SPJ1
BaCl2(aq)+Na2SO4(aq)⟶BaSO4(s)+2NaCl(aq)
Using the balanced chemical equation, determine how many moles of NaCl will be produced, if 0.731 mol of BaCl2 is allowed to react with an excess of Na2SO4.
Answer:
1.46 moles NaCl
Explanation:
To find the moles of NaCl, you need to multiply the given value (0.731 moles BaCl₂) by the mole-to-mole ratio of the two relevant molecules. This ratio is made up of the coefficients in the balanced reaction. The numerator should contain moles NaCl to allow for the cancellation of moles BaCl₂. The final answer should have 3 sig figs to reflect the given value.
1 BaCl₂(aq) + Na₂SO₄(aq) ---> BaSO₄(s) + 2 NaCl(aq)
0.731 mole BaCl₂ 2 moles NaCl
--------------------------- x ------------------------- = 1.46 moles NaCl
1 mole BaCl₂
If 0.731 mol of BaCl₂ is allowed to react with an excess of Na₂SO₄, 1.462 moles of NaCl will be produced.
The balanced chemical equation is:
BaCl₂(aq) + Na₂SO₄(aq) → BaSO₄(s) + 2NaCl(aq)
The mole ratio of BaCl₂ to NaCl is 1:2. This means that 1 mole of BaCl2 will produce 2 moles of NaCl.
Moles of BaCl₂ = 0.731 mol
Mole ratio BaCl₂:NaCl = 1:2
Moles of NaCl = 0.731 mol * 2 = 1.462 mol
If we have 0.731 moles of BaCl₂, then we will produce 2 * 0.731 = 1.462 moles of NaCl.
Therefore, 1.462 moles of NaCl will be produced.
To know mroe about NaCl:
https://brainly.com/question/33606201
#SPJ3
A sample of 0.0084 mol of HCl is dissolved in water to make a 1500 mL solution. Calculate the molarity of the HCl solution, the [H3O+] and the pH. For a strong acid such as HCl, the [H3O+] is the same as the molarity of the HCl solution.
A solution prepared by dissolving 0.0084 moles of HCl in 1500 mL of solution has a Molarity of HCl of 5.6 × 10⁻³ M, a Molarity of H₃O⁺ of 5.6 × 10⁻³ M and a pH of 2.3.
What is Molarity ?Molarity (M) is the amount of a substance in a certain volume of solution. Molarity is defined as the moles of a solute per liters of a solution. Molarity is also known as the molar concentration of a solutionA solution is prepared by dissolving 0.0084 moles of HCl in 1500 mL of solution. The molarity of HCl is:
[HCl] = 0.0084 moles / 1.5 L
= 5.6 × 10⁻³ M
HCl is a strong acid according to the following equation.
HCl(aq) + H₂O(l) ⇒ Cl⁻(aq) + H₃O⁺(aq)
Thus, the concentration of H₃O⁺ will be equal to the initial concentration of HCl, 5.6 × 10⁻³ M.
Now, we will calculate the pH of the solution using its Formula ;
pH = - log[H₃O⁺]
= - log [5.6 × 10⁻³]
= 2.3
Hence, A solution prepared by dissolving 0.0084 moles of HCl in 1500 mL of solution has a Molarity of HCl of 5.6 × 10⁻³ M, a Molarity of H₃O⁺ of 5.6 × 10⁻³ M and a pH of 2.3.
Learn more about pH here ;
brainly.com/question/14950262
#SPJ1
When did China's earliest civilization originate?
Answer:
The Chinese civilization really has an exact chronology, and the historical period began in the first year of the Western Zhou Dynasty in 841 BC. Before that, only the lineage records of the kings were recorded. Therefore, the earliest origin of Chinese civilization has not yet been finalized. Although there are many records about the Xia Dynasty in the traditional literature, due to the late completion of the book, there is no recognized evidence of the existence of the Xia Dynasty and its previous history. Therefore, some people in the modern and modern historical circles have always questioned the existence of the Xia Dynasty. sex.
Explanation:
Arrange the following elements in order of decreasing atomic radius: Ba , Sn , Cl , Pb , Se .
Rank elements from largest to smallest.
Answer:
Ba, Pb, Sn, Se, Cl
Explanation:
The atomic radius increases when going right to left and top to bottom on the periodic table and decreases going the opposite way so I put it in order based on that.
For the reaction below determine the ▲H for the reaction and state whether the reaction was endothermic or exothermic. Show your work.
C2H5OH + 3 O2 → 2 CO2 + 3H2O
C-C = 83 kcal; C-H = 99 kcal; C-O = 84 kcal; O-H = 111 kcal; C=O 192 kcal; O=O = 119 kcal
I got stuck on this and need help please, thank you so much!
Answer:exothermice
Explanation: it is relaeing heat not keeping it in
A 1dm3 solution was made by mixing 0.0040 mol of HCl(aq) and 0.0025 mol of NaOH(aq). What was the pH of the resulting solution?
The pH of the resulting solution is 2.82.
What is pH ?pH is the measure of acidity and alkalinity of a solution , It has a range of 1 to 14.
HCl + NaOH → NaCl + H₂O
0.0040 .0025 0 0
0.0040 -0.0025 0 0.0025 0.0025
Moles of HCl = 0.0015
As 0.0025 moles of NaOH reacts with 0.0025 moles of HCl leaving behind 0.0015 moles of HCl
Concentration of HCl = 0.0015/ 1 = 0.0015 M
[ H⁺] = 0.0015 M
pH = -log [ H⁺]
pH = -log [ 0.0015]
pH = 2.82
Therefore the pH of the resulting solution is 2.82.
To know more about pH
https://brainly.com/question/15289741
#SPJ1
What is the volume occupied by 14.3 g of argon gas at a pressure of 1.35 atm and a temperature of 436 K?
Answer:
9.487 L
Explanation:
argon mole wt = 39.948 gm/mole
14.3 gm / 39.948 gm/mole = .357965 moles of argon
Use Ideal Gas Law:
PV = n RT where R = .082057 L-atm / K-mol
V = .357965 * .082057 * 436 / 1.35 = 9.487 L
question is hard an di do not how to satrt thank you if you can help
The number of moles of N₂ contained in the flask will be 0.607.
What is Boyle's law?According to Boyle's law, the pressure of a gas tends to drop as the capacity of the container increases. The ideal gas equation is formed from the Boyles and Charles law.
Given data,
Pressure,P= 2.86 ATM
Volume,V = 5.00 L
Universal gas constant,R= 0.08206 L atm/mol K
Temperature,T= 13.86 °C = 286.8 K
From the ideal gas equation;
PV=nRT
2.86 × 5 = n × 0.08206 × 286.8
n = 0.607 moles
Hence the number of moles of N₂ contained in the flask will be 0.607.
To learn more about Boyle's rule refer;
https://brainly.com/question/23715689
#SPJ1
