Answer:
[Sr(OH)₂] = 0.699 M in Sr(OH)₂ sol'n (1 sig. fig)
Explanation:
Concentrated-1 Sr(OH)₂ = M₁ = unknown Concentration-2 HCl = M₂ = 0.350M
Volume of Concentrate = V₁ = 15ml Volume of Diluted = V₂ = 29.8ml
Using the Dilution Equation
Molarity x Volume of Concnt'd Soln = Molarity x Volume of Diluted Soln
From definition of molarity (M) = moles solute / volume of solution in Liters
=> moles solute = Molarity x Volume in liters*
*Note: if volume units are the same on both sides of the dilution equation then one may retain the volume in ml.
M₁ x V₁ = M₂ x V₂
=> 15ml · [Sr(OH)₂] = 30ml X 0.350M HCl soln
=> [Sr(OH)₂] = 29.8ml X 0.350M / 15ml = 0.695333... (calculator answer)
=> [Sr(OH)₂] = 0.7 M in Sr(OH)₂ sol'n (1 sig. fig)
__________________________________
work check:
M₁ x V₁ = M₂ x V₂
0.6953M x 15ml = 0.35M x 29.8ml
10.43 moles = 10.43 moles QED
The pH of an acidic solution is 5.59. What is [H+]?
Answer:
[H⁺] = 2.57x10⁻⁶ M
Explanation:
This problem can be solved using the definition of pH:
pH = -log[H⁺]
Now we isolate [H⁺] in the equation:
-pH = log[H⁺]
[tex]10^{-pH}[/tex]=[H⁺]
As we are given the pH by the problem, we can now proceed to calculate the [H⁺]:
[H⁺] = [tex]10^{-5.59}[/tex]
[H⁺] = 2.57x10⁻⁶ M
Thus, when the pH of a solution is 5,59; the molar concentration of H⁺ species is 2.57x10⁻⁶.
Composition of the air breathed in and the air breathed out changes
Answer:
breathed in air contains oxygen while breathed out air contains higher percentage of CO2
A scientist has two substances that she is testing in her lab: a pink
substance and a green substance. At room temperature, both substances
are liquids. The scientist transferred the same amount of energy into both
substances. She finds only the pink substance changed phase. How is the
pink substance different from the green substance? The pink substance
has a ...*
weaker attraction between its molecules than the green substance. Its molecules now
move away from each other.
weaker attraction between its molecules than the green substance. Its molecules now
move in place.
stronger attraction between its Molecules than the green substance. Its molecules
now move away from each other.
stronger attraction between its molecules than the green substance. Its molecules
move around each other.
Answer:
Weaker attraction between its molecules than the green substance. It's molecules now move away from each other.
Explanation:
Liquid to gas.
The pink substance should be weaker attraction between its molecules than the green substance. It's molecules now move away from each other.
The following information should be considered:
The pink substance considered to the weaker attraction that lies between the molecules as compared to the green substance. It is move away from each other, Also it is liquid to gas.Learn more: brainly.com/question/17429689
Rock formations are sculpted into shape by two general forces. What are these?
a.photosynthesis and volcanism
b.weathering and erosion
c.volcanism and weathering
d.uplift and rainfall
Answer:weathering and erosion
Please mark brainlyest
Explanation:
Answer:
b.weathering and erosion
Explanation:
Weathering and erosion shape rock formations.
I GIVE 40 POINTS PLZ ANSWER
Order the following aqueous solutions from lowest freezing point to highest freezing point: 1 M NaNO3, 1 M Li3PO4, 1 M Ca(NO3)2, 1 M C6H12O6s
Answer:
1 M C6H1206s
1 M NaNO3
1 M Ca(NO3)2
1 M Li3PO4
Explanation:
Hope it helps!
The order of solutions from lowest freezing point to highest freezing point of the given compounds are Li₃PO₄ < Ca(NO₃)₂ < NaNO₃ < C₆H₁₂O₆.
How we calculate the depression in freezing point?Depression in freezing point will be calculated from the following reaction as:
ΔTf = i × Kf × m, where
ΔTf = change in freezing point
i = Vant Hoff factor
Kf = freezing constant
m = concentration in terms of molality
In the question concentration of compounds are given in molarity and for all compounds it is same, so the depression in freezing point will directly depends on the Vant Hoff factors of given compounds.
Vant Hoff factor for NaNO₃ is 2.Vant Hoff factor for Li₃PO₄ is 4.Vant Hoff factor for Ca(NO₃)₂ is 3.Vant Hoff factor for C₆H₁₂O₆(s) is 1.From the above data it is clear that Li₃PO₄ will have the lowest freezing point and C₆H₁₂O₆ will have the highest and sequence from lowest to highest will be shown as:
Li₃PO₄ < Ca(NO₃)₂ < NaNO₃ < C₆H₁₂O₆.
Hence the required order is Li₃PO₄ < Ca(NO₃)₂ < NaNO₃ < C₆H₁₂O₆.
To know more about Vant Hoff factor, visit the below link:
https://brainly.com/question/22047232
Radium-222 undergoes radioactive decay to produce radon-218. Which
particle needs to be added to this equation to show that the total numbers of
neutrons and protons are not changed by the reaction?
22 Ra
21°Ra + ?
88
86
A. He
B. o
tie
c. Le
D. He
Answer:
2/4 HE
Explanation:
Ape.x
Lily is doing a science experiment with a substance in a sealed jar. At first,
the substance's molecules are moving around each other. What will
happen to Lily's substance if she transfers energy into the substance and
causes a phase change? After the phase change, the substance's
molecules will move...'
faster, and the substance will be a liquid.
faster, and the substance will be a gas.
slower, and the substance will be a solid.
slower, and the substance will be a liquid.
Answer:
Faster, and the substance will be a gas.
Explanation:
I'm quite not sure with it. But, I've tried my best. Since maybe the substance is liquid
In an aqueous solution at 25°C, if [H30+] = 3.3 * 10^4 M, then [OH-] is:
Answer:
[OH-] = 3.0 x 10^-19 M
Explanation:
[H3O+][OH-] = Kw
Kw = 1.0 x 10^-14
[H3O+][OH-] = 1.0 x 10^-14
[OH-] = 1.0 x 10^-14 / 3.3 x 10^4 = 3.0 x 10^-19
when the energy is released what happens to the energy of the system
Answer:
Whether a chemical reaction absorbs or releases energy, there is no overall change in the amount of energy during the reaction. That's because energy cannot be created or destroyed. This is the law of conservation of energy.
True or False: Having a greater volume definitely means a lower concentration (molarity) solution
Having a greater volume definitely means a lower concentration (molarity) of solution. So, the statement is true.
What is meant by molarity of a solution ?Molarity of a solution is defined as the number of moles of solute present per unit volume of solution.
Here,
Since, the number of moles of solute in one litre of solution is known as the molarity, we can say that the change in volume of the solution will affect the molarity of the solution.
Molarity, M = n/V
where n is the number of moles of solute and V is the volume of solution
From the equation, we can say that the molarity of the solution is inversely proportional to its volume.
We know that, molarity of a solution is a temperature dependent parameter.
As the volume of the solution increases, the temperature also increases( Volume [tex]\alpha[/tex] Temperature). When the temperature increases, it affects the molarity of the solution such that the number of moles remains constant and as a result of the increasing volume, the molarity decreases.
Hence,
Having a greater volume definitely means a lower concentration (molarity) of solution.
To learn more about molarity, click:
https://brainly.com/question/29884686
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a chemical formula is made up of carbon and oxygen. they have 27% and 73% respectively.
A.what is the empirical formula of the chemical substance?
B.name the compound you identified in A above.
Answer:
A. CO₂
B. carbon dioxide
Explanation:
To determine the empirical formula of a compound, we need to follow a series of steps.
Step 1: Divide each mass percent by the atomic mass of the element
C: 27/12.01 = 2.25
O: 73/16.00 = 4.56
Step 2: Divide all the numbers by the smallest one, i.e., 2.25
C: 2.25/2.25 = 1
O: 4.56/2.25 ≈ 2
The empirical formula of the compound is CO₂. The name of this compound is carbon dioxide.
Which of the following equations correctly describes how to calculate net income? a. net income = (cost of goods sold) - (net sales) - (operating expenses) b. net income = (operating expenses) - (cost of goods sold) - (net sales) c. net income = (operating expenses) + (cost of goods sold) - (net sales) d. net income = (net sales) - (cost of goods sold) - (operating expenses) Please select the best answer from the choices provided A B C D Mark this and return
Answer:
The answer is D. net income= (net sales) - (cost of goods sold)- (operating expenses).
Explanation:
How
many mols are in 151 g of dinitrogen monoxide?
Answer:
3.43 moles
Explanation:
To convert moles into grams you must take the number of grams and divide it by the atomic mass of the compound.
in this case, grams is 151 and N2O has an atomic mass of 44.013
so your equation would look like
151/44.013=3.430804535
your answer would be 3.43 moles
Is liquid ammonia a household acid?
Yes it is an cleaning product
Answer:
yes
Explanation:
it cleans in the house
What can happen to a rock when water flows through cracks or holes in the rock?
Answer:
it will crack because if the water inside of a rock freezes the water would start to expand and start stretching it causing it to break
Explanation:
2Fe(s) +3H2SO4(aq) →Fe2(SO4)3(aq) +3H2(g)When 10.3 g of iron are reacted with 14.8 moles of sulfuric acid, what is the percent yield if 5.40 g of "hydrogen gas" are collected?
Answer:
1040%
Explanation:
To solve this question we must convert the mass of Iron to moles in order to find limiting reactant. With limiting reactant we can find the theoretical moles of hydrogen and theoretical mass:
Percent yield = Actual yield (5.40g) / Theoretical yield * 100
Moles Fe -Molar mass: 55.845g/mol-:
10.3g * (1mol / 55.845g) = 0.184 moles of Fe will react.
For a complete reaction of these moles there are necessaries:
0.184 moles Fe* ( 3 mol H2SO4 / 2 mol Fe) = 0.277 moles H2SO4.
As there are 14.8 moles of the acid, Fe is limiting reasctant.
The moles of H2 produced are:
0.184 moles Fe* ( 3 mol H2 / 2 mol Fe) = 0.277 moles H2
The mass is:
0.277 moles H2 * (2.016g/mol) = 0.558g H2
Percent yield is:
5.40g / 0.558g * 100 = 1040%
It is possible the experiment wasn't performed correctly
C. 2.86 g
D. 1.22 g
13. At what Kelvin temperature will 25.2 mol of Xe occupy a volume of 645 L at a pressure of 732 torr?
A. 361 K
B. 291 K
C. 402 K
D. 300 K
Add an oxide ion to Fe2O3
Answer:
Iron Oxide (Fe2O3) also known as rust is also an ionic bond, it has metallic compound Iron (Fe) which contains positively charged cations and it has nonmetallic compound Oxygen (O) which contains negatively charged anions.
Explanation:
i hope it help
Where is chemical energy contained in a compound?
A. in the movement of the electrons
B. in the nuclei
C. in the bonds
D. in unbonded electrons
Answer:
C
Explanation:
Energy stored in the bonds of chemical compounds. Chemical energy may be released during a chemical reaction, often in the form of heat; such reactions are called exothermic.
Answer:
The Answer is C.
Explanation:
Cause I'm smart
The melting of ice is considered a/an _______ because the ice absorbs heat from the surroundings.
Question 3 options:
A)
chemical reaction
B)
thermochemical process
C)
exothermic process
D)
endothermic process
Answer:
the correct answer is D
Explanation:
Basically, melting ice is an endothermic reaction because the ice absorbs (heat) energy, which causes a change to occur.
A chemist prepares a solution of silver(I) nitrate AgNO3 by measuring out 62.3μmol of silver(I) nitrate into a 50.mL volumetric flask and filling the flask to the mark with water.
Calculate the concentration in /molL of the chemist's silver(I) nitrate solution. Be sure your answer has the correct number of significant digit
*please write the answer without any files disturbance*
Answer:
0.0012 mol/L.
Explanation:
From the question given above, the following data were obtained:
Number of mole of AgNO₃ = 62.3 μmol
Volume = 50 mL
Molarity of AgNO₃ =?
Next, we shall convert 62.3 μmol to mole. This can be obtained as follow as follow:
1 μmol = 10¯⁶ mole
Therefore,
62.3 μmol = 62.3 × 10¯⁶
62.3 μmol = 62.3×10¯⁶ mole
Next, we shall convert 50 mL to L. This can be obtained as follow:
1000 mL = 1 L
Therefore,
50 mL = 50 mL × 1 L / 1000 mL
50 mL = 0.05 L
Finally, we shall determine the concentration of AgNO₃ in mol/L as follow:
Number of mole of AgNO₃ = 62.3×10¯⁶ mole
Volume = 0.05 L
Molarity of AgNO₃ =?
Molarity = mole /Volume
Molarity of AgNO₃ = 62.3×10¯⁶ / 0.05
Molarity of AgNO₃ = 0.0012 mol/L
Thus, the concentration of AgNO₃ is 0.0012 mol/L
For each of the following precipitation reactions, complete and balance the equation, indicating clearly which product is the precipitate.
a) Ba(NO3)2(aq) + (NH4)2SO4(aq) -->
b)CoCl3(aq) + NaOH(aq) -->
c)FeCl3(aq) + (NH4)2SS(aq) -->
Answer:
pagtoon og imo dots
Explanation:
pagtoon og imo dots
Which best describes what happens during a typical energy conversion?
A. Some energy is destroyed.
B. Some energy is created.
C. The total amount of all forms of energy stays the same.
D. Some mass changes into energy, and some energy changes into
mass.
The best answer for your question would be C. The total amount of all forms of energy stays the same.
First, let's eliminate the wrong choices. According to the Law of Conservation of Energy, you cannot create nor destroy energy, so you can eliminate choices A and B.
Also according to the Law of Conservation of Energy, the total amount of energy will always be the same. It may transform into different forms of energy.
To me, D doesn't sound very correct. For this one you can take an aducational guess, but I do not believe it would be D.
Hope this helps; have a great day!
A substance has a percent composition of 17.55% Sodium, 39.70%
Chromium, and 42.75% Oxygen. What is the empirical formula of the
substance? *
Need help anyone plz :)
Cr2Na2O7
Sodium Dichromate
A 50.0 mL sample of buffer solution contains 0.120 M acetic acid and 0.150 M sodium acetate. If 5.55 mL of 0.092 M NaOH is added to this solution, identify the resulting number of moles of acetic acid, sodium acetate, and NaOH.
Answer:
see calculations below
Explanation:
Given: HOAc ⇄ [H⁺] + [OAc⁻]
C(i) 0.12M 0M 0.15M
mix => 5.55ml(0.092M NaOH) / (50ml + 5.55ml)
= 0.00555(0.092)mole NaOH / 0.0555 L Soln
= 0.0092M in NaOH is added into the initial buffer solution
= 0.0092M in OH⁻ (NaOH is a strong base => 100% ionized)
Rxn => Addition of 0.0092M OH⁻ will react with 0.0092M H⁺ shifting buffer . equilibrium to the right decreasing [HOAc] and increasing [OAc⁻] by . 0.0092M each.
Therfore ...
Given: HOAc ⇄ [H⁺] + [OAc⁻]
C(i) 0.12M 0M 0.15M
ΔC - 0.0092M +x +0.0092M
C(f) 0.1108M x 0.1592M => New Concentrations . after adding 0.0092M . NaOH
Substituting new acid and ion concentrations into Ka expression ...
Ka = [H⁺][OAc⁻]/[HOAc] = (x)(0.1592M)/(0.1108M) = 1.75 x 10⁻⁵M
=> x = [H⁺](new) = (1.75 x 10⁻⁵M*)(0.1108M)/(0.1592M) = 1.22 x 10⁻⁵M in H⁺ ions
*units of Ka are Molar
FYI => Adding a strong base to a buffer solution will shift pH to more basic.
Adding a strong acid to a buffer solution will shift pH to more acidic.
=> (such is a good way to check that your buffer calculations are correct.)
NOTE => Question asks for moles of HOAc, Na⁺OAc⁻ & NaOH after adding base. Giving answers in terms of Molarity (moles/Liter) is same as moles. Therefore ...
[HOAc] = 0.1108M
[NaOAc] = 0.1592M
[NaOH] = ∅M (from rxn of H⁺ + OH⁻ => H₂O, all NaOH was consumed in acid/base reaction. Remaining are only Na⁺ as a spectator ion and OH⁻ as a function of the new concentration of H⁺ => [OH⁻] = Kw/[H⁺] = 1 x 10⁻¹⁴/1.22 x 10⁻⁵ = 8.2 x 10⁻¹⁰M.
Hope this helps. :-)
When the concentration of reactant molecules is increased
Complete question is;
When the concentrations of reactant molecules are increased, the rate of reaction increases. The best explanation for this phenomenon is that as the reactant concentration increases,
A)the average kinetic energy of molecules increases.
B)the frequency of molecular collisions increases.
C)the rate constant increases.
D)the activation energy increases.
E)the order of reaction increases.
Answer:
B) The frequency of molecular collisions increases.
Explanation:
When we increase number of reactant molecules, the effective collision between the reactant molecules will form a product which also increases. As a result, the overall rate of the reaction will also increase which means the frequency of the molecular collision will also increase as well.
Thus, the correct answer is Option B
A potential energy diagram is shown. What is the activation energy of this reaction?
a. 50 kJ
b. 100kJ
c. 150kJ
d. 200kJ
Answer: a. 50 kJ
Explanation: good luck
3,01 x 10^23molecules H.O
Answer:
Therefore Mass of 6.022 x10^23 molecules= 32 g.
Explanation:
How many moles of O2 are dissolved n 10.0 L of a 0.001 mol dm-3 solution?
Answer:
[tex]0.01molO_2[/tex]
Explanation:
Hello there!
In this case, by considering the definition of molar solution as the moles of solute over volume in liters or cubic meters of solution, we can see that actually 10.0 L of the solution are equal to 10.0 dm³. In such a way, since the concentration is 0.001 mol / dm³, the moles of oxygen that are dissolved turn out to be:
[tex]0.001mol/dm^3 * 10.0dm^3\\\\0.01molO_2[/tex]
Best regards!
Using standard heats of formation, calculate the standard enthalpy change for the following reaction.
2H2(g) + O2(g)
—>2H20(9)
Answer:
ΔH°r = -483.64 kJ
Explanation:
Let's consider the following balanced equation.
2 H₂(g) + O₂(g) ⇒ 2 H₂O(g)
We can calculate the standard enthalpy change of the reaction (ΔH°r) using the following expression.
ΔH°r = ∑ΔH°f(p) × np - ∑ΔH°f(r) × nr
where
ΔH°f: standard heat of formation
n: moles
p: products
r: reactants
ΔH°r = ΔH°f(H₂O(g)) × 2 mol - ΔH°f(H₂(g)) × 2 mol - ΔH°f(O₂(g)) × 1 mol
ΔH°r = (-241.82 kJ/mol) × 2 mol - 0 kJ/mol × 2 mol - 0 kJ/mol × 1 mol
ΔH°r = -483.64 kJ