Answer:
Here's what I get
Explanation:
(a) Mass % of each ion
I used this template to calculate the percentages in the table below.
<u> Ion Abundance Mass % </u>
Na⁺ 10 560 30.72
K⁺ <u> 380 </u> <u> 1.11 </u>
Alkali metals 10 940 31.82
Mg²⁺ 1 270 3.69
Ca²⁺ <u>400 </u> <u> 1.16 </u>
Alkaline earth metals <u>1 670 </u> <u> 4.86 </u>
Total metal ions 12 610 36.68
Cl⁻ 18 980 55.20
SO₄²⁻ 2 650 7.71
HCO₃⁻ 140 0.41
Anions <u>21 770 </u> <u> 63.32
</u>
TOTAL 34 380 100.00
(b) 30.72 % of the total mass is sodium ion.
(c) Alkaline earth metals vs alkali metals
The mass percent of alkali metal ions is 6.55 times that of alkaline earth metal ions.
(d) The mass of anions is greater than that of cations.
Answer:
k = ![\frac{[HOCl]^2}{[Cl]^2}](https://tex.z-dn.net/?f=%5Cfrac%7B%5BHOCl%5D%5E2%7D%7B%5BCl%5D%5E2%7D)
Explanation:
The equilibrium-constant expression is defined as the ratio of the concentration of products over concentration of reactants. Each concentration is raised to the power of their coefficient.
Also, pure solid and liquids are not included in the equilibrium-constant expression because they don't affect the concentration of chemicals in the equilibrium
The global reaction is:
2 HgO (s) + H₂O (l) +2 Cl₂ (g) ⇌ 2 HOCl (aq) + HgO⋅HgCl₂ (s)
Thus, equilibrium-constant expression is:
<em>k = </em>
You don't include HgO nor HgO⋅HgCl₂ because are pure solids nor water because is pure liquid.
I hope it helps!
<span>15.4 milligrams
The ideal gas law is
PV = nRT
where
P = pressure of the gas
V = volume of the gas
n = number of moles of gas
R = Ideal gas constant (8.3144598 L*kPa/(K*mol) )
T = absolute temperature.
So let's determine how many moles of gas has been collected.
Converting temperature from C to K
273.15 + 25 = 298.15 K
Converting pressure from mmHg to kPa
753 mmHg * 0.133322387415 kPa/mmHg = 100.3917577 kPa
Taking idea gas equation and solving for n
PV = nRT
PV/RT = n
n = PV/RT
Substituting known values
n = PV/RT
n = (100.3917577 kPa 0.195 L) / (8.3144598 L*kPa/(K*mol) 298.15 K)
n = (19.57639275 L*kPa) / (2478.956189 L*kPa/(mol) )
n = 0.007897031 mol
So we have a total of 0.007897031 moles of gas particles.
Now let's get rid of that percentage that's water vapor. The percentage of water vapor is the vapor pressure of water divided by the total pressure. So
24/753 = 0.03187251
The portion of hydrogen is 1 minus the portion of water vapor. So
1 - 0.03187251 = 0.96812749
So the number of moles of hydrogen is
0.96812749 * 0.007897031 mol = 0.007645332 mol
Now just multiple the number of moles by the molar mass of hydrogen gas. Start with the atomic weight.
Atomic weight hydrogen = 1.00794
Molar mass H2 = 1.00794 * 2 = 2.01588 g/mol
Mass H2 = 2.01588 g/mol * 0.007645332 mol = 0.015412073 g
Rounding to 3 significant figures gives 0.0154 g = 15.4 mg</span>
Answer:
0.3229 M HBr(aq)
0.08436M H₂SO₄(aq)
Explanation:
<em>Stu Dent has finished his titration, and he comes to you for help with the calculations. He tells you that 20.00 mL of unknown concentration HBr(aq) required 18.45 mL of 0.3500 M NaOH(aq) to neutralize it, to the point where thymol blue indicator changed from pale yellow to very pale blue. Calculate the concentration (molarity) of Stu's HBr(aq) sample.</em>
<em />
Let's consider the balanced equation for the reaction between HBr(aq) and NaOH(aq).
NaOH(aq) + HBr(aq) ⇄ NaBr(aq) + H₂O(l)
When the neutralization is complete, all the HBr present reacts with NaOH in a 1:1 molar ratio.
<em>Kemmi Major also does a titration. She measures 25.00 mL of unknown concentration H₂SO₄(aq) and titrates it with 0.1000 M NaOH(aq). When she has added 42.18 mL of the base, her phenolphthalein indicator turns light pink. What is the concentration (molarity) of Kemmi's H₂SO₄(aq) sample?</em>
<em />
Let's consider the balanced equation for the reaction between H₂SO₄(aq) and NaOH(aq).
2 NaOH(aq) + H₂SO₄(aq) ⇄ Na₂SO₄(aq) + 2 H₂O(l)
When the neutralization is complete, all the H₂SO₄ present reacts with NaOH in a 1:2 molar ratio.
Here we have to get the correct statements among the given, applicable for Diels-Alder reaction.
The true statements in case Diels-Alder reaction are-
1. An excess of Maleic anhydride is used.
2. The I.R. of the products are indistinguishable.
The Diels-Alder reaction is the most is the most important cyclo-addition reaction in organic chemistry. These are addition reactions in which ring systems are formed without eliminating any compounds.
There remains one diene and one dienophile. The reaction is reversible in nature and requires elevated temperature to obtain its transition state. The reaction rate become faster in certain condition like using of polar solvents.
Among the given statements the following statements are true-
1. An excess of maleic anhydride (the most effective di-enophile) is used to process the reaction in forward direction.
2. The products obtain in this reaction are stereoisomers thus are indistinguishable by infrared spectroscopy (IR).
The statements which are not true for the Diels-Alder reaction:
3. The re-crystallization of the products by any polar solvent like methanol is not feasible as it will cause the retro reaction due to stability of the transition state in polar solvent.
4. Cleaning of glassware are compulsory for any reaction it is not specifically true for Diels-Alder reaction.
5. The reaction occurs at elevated temperature thus flame is required.
