Answer:
17.95 g
Explanation:
The electrolysis of CaBr₂ → Ca²⁺ + 2Br⁻
Ca₂⁺ + 2e⁻ → Ca
Recall that:
Charge (Q) = current (I) × time (t)
Q = 10.0 × 2.4 × 3600
Q = 86400 C
Number of moles of electron = [tex]\dfrac{charge \ Q}{faraday's \ constant}[/tex]
[tex]=\dfrac{86400}{96485} \\ \\ =0.8955 \ mol[/tex]
No of moles of Ca = [tex]\dfrac{1}{2} \times 0.8955[/tex]
= 0.44775 moles
Mass of Ca = no of moles × molar mass of Ca
= 0.44775 mol × 40.08 g/mol
= 17.95 g
how much alum product would be lost to the crystallization solution if you had 42.5 ml of solution after filtration and the solubility of alum is approximately 2.63 g alum in 100 ml of 0 degrees celcius acidic water
Answer:
Total amount of alum lost = 0.5122 grams
Explanation:
Let the total volume of the solution be 100 mL
In 100 mL of solution, there is 2.63 gram of alum.
Out of this 100 mL solution, 42.5 mL is remaining.
Amount of alum in 42.5 mL solution is
[tex]\frac{42.5}{100} * 2.63 = 1.117\\[/tex] grams
Now the amount of alum lost is [tex]2.63 -1.117 = 0.5122[/tex] grams
A gas sample has a volume of 185 mL at 45°C. What is its volume at 109°C?
Answer:
342 mL
Explanation:
From the question given above, the following data were obtained:
Initial volume (V₁) = 185 mL
Initial temperature (T₁) = 45 °C
Final temperature (T₂) = 109 °C
Final volume (V₂) =?
Next, we shall convert celsius temperature to Kelvin temperature. This can be obtained as follow:
T(K) = T(°C) + 273
Initial temperature (T₁) = 45 °C
Initial temperature (T₁) = 45 °C + 273
Initial temperature (T₁) = 318 K
Final temperature (T₂) = 109 °C
Final temperature (T₂) = 109 °C + 273
Final temperature (T₂) = 382 K
Finally, we shall determine the final volume of the gas as follow:
Initial volume (V₁) = 185 mL
Initial temperature (T₁) = 318 K
Final temperature (T₂) = 382 K
Final volume (V₂) =?
V₁/T₁ = V₂/T₂
285 / 318 = V₂ / 382
Cross multiply
318 × V₂ = 285 × 382
318 × V₂ = 108870
Divide both side by 318
V₂ = 108870 / 318
V₂ ≈ 342 mL
Therefore, the new volume of the gas is 342 mL
Answer:
342 mL
Explanation:
Hope this helps
A/An ______ bond occurs when 2 atoms share electrons.
O ionic
O covalent
O James
O electrical
Answer:
convalent???????
Explanation:
sowwy if it wrong
copper chloride reacts with magnesium but magnesium chloride does not react with copper. Why is this?
Answer:
Mg is highly reactive as compared to that of Copper owing to its periodic position
Explanation:
MG lies in the second column of the periodic table while Cu lies in the 11th column of the periodic table from the left.
The elements in the first two columns are metallic in nature are highly reactive.
In CuCl2 solution, Mg being highly reactive replaces Cu but in MgCl2 solution, Cu being less reactive in nature do not replaces the Mg from the solution.
Define What is boiling
Answer:
Boiling is the rapid vaporization of a liquid, which occurs when a liquid is heated to its boiling point, the temperature at which the vapour pressure of the liquid is equal to the pressure exerted on the liquid by the surrounding atmosphere.
Explanation:
Hi
Explain the nitrogen cycle I need a 6th grade answer please
Answer:
The nitrogen cycle is a repeating cycle of processes during which nitrogen moves through both living and non-living things: the atmosphere, soil, water, plants, animals and bacteria. In order to move through the different parts of the cycle, nitrogen must change forms.
Explanation:
Warm air rises because it A. lacks density. B. has a higher density than cool air. C. has a lower density than cool air. D. is unaffected by pressure.
Answer:
b
Explanation:
You have a solution of NaOH that is 3.0 M. If you need 250 mL of a 1.5 M solution, what volume of the stock solution should you use?
Answer:
answer is 30 g!!!!!!!!!
A biochemist carefully measures the molarity of salt in 23.5mL of photobacterium cell growth medium to be 7.73 mM. Unfortunately, a careless graduate student forgets to cover the container of growth medium and a substantial amount of the solvent evaporates. The volume of the cell growth medium falls to 4.78mL. Calculate the new molarity of salt in the photobacterium cell growth medium.
Round each of your answers to 3.
Answer: The new molarity of salt in the photobacterium cell growth medium is 38.0 mM
Explanation:
According to the dilution law,
[tex]M_1V_1=M_2V_2[/tex]
where,
[tex]M_1[/tex] = molarity of concentrated solution = 7.73 mM
[tex]V_1[/tex] = volume of concentrated solution = 23.5 ml
[tex]M_1[/tex] = molarity of diluted solution = ?
[tex]V_1[/tex] = volume of diluted solution = 4.78 ml
Putting in the values we get:
[tex]7.73\times 23.5=M_2\times 4.78[/tex]
[tex]M_2=38.0mM[/tex]
Therefore, new molarity of salt in the photobacterium cell growth medium is 38.0 mM
Use the following reaction:
4Fe + 3O2 → 2Fe2O3
If you have 6.8 mol of Fe, how much Fe2O3 (in moles) would you make?
Which of the following reactions best describes the acid-base properties of acetic acid (CH3COOH) in an aqueous solution? O CH3COOH(aq) + 4H2O(l) 4H30+ (aq) + C2024-(aq) (reversible reaction) O CH3COOH(aq) + H2O(l) H3O+(aq) + CH3COO-(aq) (reversible reaction) O CH3COOH(aq) + H2O(1) CH3C00* (aq) + OH(aq) (reversible reaction) -> H2O*(aq) + O CH3COOH(aq) + H2O() CH3COO-(aq) O CH3COOH(aq) + H2O(0) + OH(aq) -> CH3COO(aq)
Answer:
CH3COOH(aq) + H2O(l) ⇄ CH3COO-(aq) + H3O+(aq)
Explanation:
Acetic acid is a weak acid, so it only partially dissociates, hence the reversible reaction. Acids react with water to produce conjugate base and hydronium.
Vines most successfully compete for sunlight in tropical rainforests by _______.
a.
climbing up into the canopy
b.
strangling the trees they grow on
c.
having broader leaves that absorb more light
d.
having thick, woody stems
Answer:
climbing up into the canopy
Explanation:
An Introduction To Chemistry
Answer Sheet
Please provide your answer in the answer sheets!
1
18
2
19
3
20
4
21
5
22
6
23
7
24
8
25
9
26
10
27
11
28
12
29
13
30
14
31
15
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17
An Introduction To Chemistry
1. During his distinguished career this scientist received two unshared Nobel prizes. One for chemistry and one for peace.
Alfred Nobel
Marie Currie
Linus Pauling
Albert Einstein
2. The study of matter and the changes it undergoes describes the science of ______.
physics
mathematics
chemistry
biology
3. The _________ is the fundamental unit of matter.
atom
compound
nucleus
proton
4. The atom is composed of three subatomic particles known as _____, ____ and _______.
neutrals, electives and peeons
quarks, alpha rays and xenons
electrons, protozoans and electricals
protons, neutrons and electrons
5. Protons are _________ charged particles found in the nucleus of an atom.
neutrally
positively
negatively
brighltly
6. Electrons are ________ charged particles that orbit the nucleus of an atom.
negatively
positively
neutrally
brighltly
7. Neutrons are ________ particles found in the nucleus of an atom.
negatively charged
positively charged
uncharged
brightly
8. An ion is an atom or molecule that ___________.
is electrically neutral
is composed of two or more elements
is man made
carries a charge
9. Which of the following chemical species is a cation?
Cl-
H+
Au
HCO3-
10. The atomic number of an atom or element describes the number of _______.
electrons orbiting the nucleus
neutrons in the nucleus
alpha particles in the nucleus
protons in the nucleus
11. Mass is proportional to the number of _________ that make up an object.
atoms
cells
neutrons
protons
12. Weight is best described as _____________.
the number of atoms in an object
the pull of gravity on matter
the electrical charge on an ion
the number of electons in an atom
13. Atoms of any one type of element, such as gold, all posess the same number of _______.
electrons
neutrons
protons
nuclei
14. There are currently _______ known elements.
65
98
112
152
15. Element _______ are one or two letter abbreviations for the names of the elements.
numbers
atomic numbers
symbols
characters mass
16. Two or more elements that combine as a result of a chemical reaction form _____.
atoms
ions
mixtures
compounds
17. An example of a mixture would be __________.
a bar of pure gold
the air we breathe
sodium chloride salt
pure water
18. The three states of matter are ________, ________ and _________.
atoms, molecules and compounds
atoms, compounds and mixtures
solids, liquids and gases
solids, gases and steam
19. The least dense and most energetic of the three states of matter is ____.
the gaseous state
the liquid state
the solid state
the elemental state
20. All measurements must consist of both ____________.
a size and a shape
a price and a volume
a number and a unit
a color and a number
21. Density is a physical property that refers to _____________.
the number of atoms in an object
the weight of an object
the mass of an object relative to its volume
the weight of an object relative to its cost
22. A kilogram is equal to ________ grams.
1
10
100
1,000
23. There are _______ centimeters in a meter.
1
10
100
1,000
24. Measurements are _________ because of equipment error and human judgment.
useless
uncertain
perfect
inaccurate
25. The number 221.5 contains ______ significant figure(s).
1
2
3
4
26. The number .001 contains ______ significant figure(s).
1
2
3
4
27. The number 226 would be scientifically noted as ______.
226
2.26 x101
2.26 x 102
22.6 x 101
28. The figure .005 would be scientifically noted as _______.
5 x 10-1
5 x 10-2
5 x 10-3
5 x 10-4
29. Elements or atoms are arranged on the periodic table in the order of increasing ________.
atomic mass
atomic weight
atomic number
atomic symbols
30. A substance that weighs 10 grams and has a volume of 2 cm3 would have a density of ______.
5 g/cm3
10g/cm3
2g/cm3
15g/cm3
31. The terms Kelvin, Celsius and Fahrenheit all correspond to units of _______.
density
hardness
volume
temperature
32. The ________ is the SI standard unit for measurements of length.
cetimeter
foot
meter
yard
33. One kilogram is equal to approximately ________ pounds.
1.2
2.2
3.2
4.2
1. C. Linus Pauling
2. C. chemistry
3. A. atom
4. D. protons, neutrons and electrons
5. B. positively
6. A. negatively
7. C. uncharged
8. D. carries a charge
9. C. Au
10. D. protons in the nucleus
11. A. atoms
12. B. the pull of gravity on matter
13. C. protons
14. C. 112
15. C. symbols
16. D. compounds
17. C. sodium chloride salt
18. C. solids, liquids, and gases
19. A. the gaseous state
20. C. a number and a unit
21. B. the weight of an object
22. D. 1,000
23. C. 100
24. B. uncertain
25. D. 4
26. A. 1
27.C. 2.26 x 102
28. C. 5 x 10-3
29. C. atomic number
30. A. 5 g/cm3
31. D. temperature
32. C. meter
33. B. 2.2
Copper metal reacts with nitric acid according the equation below 3 Cu (s) +8 HNO 3(aq) -...m+3 Cu^ 2+ (aq)+2NO (g) +6 NO 3 (aq)+4 H 2 O 0 What mass of NO (g) will be produced if 8.96 g of copper are reacted wtih excess nitric acid. Be sure to include units.
Answer:
i think it is NO2 and +6 NO 6 that's all I have
Gaseous ammonia, NH3, is obtained from the reaction of gaseous hydrogen and gaseous nitrogen. According to this reaction, what volume, in L, of nitrogen is required to completely react with 25.0 L of hydrogen under STP conditions?
Group of answer choices
8.32 mL
8.32 L
8.20 L
8.00 L
Answer:
8.33 L .
Explanation:
Hello there!
In this case, according to the given problem, it is possible to firstly write up the undergoing chemical reaction:
[tex]3H_2+N_2\rightarrow 2NH_3[/tex]
Whereas the mole ratio of hydrogen to nitrogen is 3:1. In such a way, given that the mole ratios can be also applied in volume when the temperature and pressure remain unchanged, it is possible to compute the required volume of nitrogen from 25.0 L of hydrogen as shown below:
[tex]25.0L\ H_2*\frac{1L \ N_2}{3L\ H_2}\\\\=8.33L[/tex]
Best regards!
Which is better frozen or frozen 2
Answer:
IN MY OPINION i think frozen 2
Explanation:
frozen 2 explained the life of elsa and anna so much better and had a great storyline imo
Answer:
i haven't seen frosen 2 yet
Explanation:
〒▽〒
How to remove candle wax?
(a)0.444 Mol of COCl2 in 0.654 L of solution
(b) 98.0 gram of phosphoric acid, H3PO4, in 100 L of solution
(c) 0.2074 g of calcium hydroxide, Ca(OH)2 in 40.00 mL of solution
(d)10.5 kg of Na2AO4.10H2O in 18.60 L of solution
(e) 7.0 x 10-3 Mol of l2 in 100.0 ml of solution
(f) 1.8 x 104 mg of HCL in 0.075 of solution
Answer is in a photo. I can only upload it to a file hosting service. link below!
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Which reaction below is a physical change?
a. CH4(g) + 2O2(g) → CO2(g) + 2HsO(l)
b. CaO(s) + H2O(l)→ Ca(OH)2(s)
c. H2O (l) → H2O(s)
D. 2HsO (l) → 2H2(g) + O2(l)
Answer:
c. H₂O (l) → H₂O(s)
Explanation:
The correct answer is option C: The molecular formulas for the substance(s) on the left side of the equation and on the right side of the equation are identical. This means that there was not a chemical change, but a physical one.
In this concrete example, what happened was a change of states of matter: from liquid (l) to solid (s).
Other reactions have different molecular formulas on both sides of the equation, thus they represent chemical changes.
Calculate the number of moles of NO in 4.10 x 1021 molecules of NO.
Answer:
.0068
Explanation:
You divided the number of molecules by 6.022*10^23 (Avagodros Number) to get the number of moles.
Which term describes a solid that comes out of a solution?
A.granules
B.precipitate
The chemical formula for propane is: CH3CH2CH3 Calculate the molar mass of propane. Round your answer to 2 decimal places.
Answer:
44.11 g/mol
Explanation:
In order to calculate the molar mass of any molecule, we need to add the molar mass of each atom that compounds it:
Molar Mass of C₃H₈ = (Molar Mass of C) * 3 + (Molar Mass of H)*8Molar Mass of C₃H₈ = (12.01) * 3 + (1.01) * 8Molar Mass of C₃H₈ = 44.11 g/molThe molar mass of propane is thus 44.11 g/mol.
Help help help help help help
If x represents the molar solubility of Ca(OH)2 , what is the correct equation for the K sp ?
Ksp=x^2
Ksp=2x^3
Ksp=4x^3
Ksp=x^3
Answer:
Ksp = 4x³
Explanation:
Step 1: Write the reaction for the solution of calcium hydroxide
Ca(OH)₂(s) ⇒ Ca²⁺(aq) + 2 OH⁻(aq)
Step 2: Make an ICE chart
Let "x" be the molar solubility of calcium hydroxide.
Ca(OH)₂(s) ⇒ Ca²⁺(aq) + 2 OH⁻(aq)
I 0 0
C +x +2x
E x 2x
Step 3: Write the expression for the solubility product constant (Ksp)
The solubility product constant is equal to the product of the concentrations of the products raised to their stoichiometric coefficients.
Ksp = [Ca²⁺] × [OH⁻]² = x × (2x²) = x × 4x² = 4x³
if [tex]x[/tex] represents the molar solubility of calcium hydroxide then correct equation for the Ksp is [tex]\bold {x^3}[/tex]
Solubility product constant Ksp:
It is the equilibrium constant for a solid substance that are dissolved in an aqueous solution. It expresses how much a solute is dissolved in solution.
The reaction of calcium hydroxide for the solution
[tex]\bold {Ca (OH )_2(s) \rightarrow Ca^2^+(aq) + 2 OH^-(aq)}[/tex]
1 mole of calcium hydroxide is dissociate into 1 mole of calcium ion and 2 moles of Hydroxil ion.
The Ksp equation for the solution,
[tex]\bold {Ksp =[Ca^2^+][ OH^-]^2}\\[/tex]
If [tex]x[/tex] represents molar solubility,
[tex]\bold {Ksp =[x][ x]^2 = x^3}\\[/tex]
Therefore, if [tex]x[/tex] represents the molar solubility of calcium hydroxide then correct equation for the Ksp is [tex]\bold {x^3}[/tex]
To know more about Ksp,
https://brainly.com/question/4736767
Of the following two gases, which would you predict to diffuse more rapidly? SO2 or CI2
Answer:
SO2 this is my answer
..wkkwks
how many liters are present in 31.998 g of O2?
Answer:
Explanation:
First calculate how many moles of O2 you have. O is 16g/mole, so O2 is 32g/mole. 50/32 = 1.5625 moles. 1 mole of any gas at stp is 22.4 liters.
1.5625 × 22.4 = 35 liters.
Its been 15 years since I graduated HS, and I still remember how to do this. Do your own homework next time and in 15 years you may be able to do the same.
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What is the pH of a 1x10-2 M NaOH solution?
a. pH = 2
b.pH = 12
c.pH = 1x10-2
d. pH = 1x10-12
Oe. None of the above
Answer:
A.
Explanation:
I hope I can help
Hahahhahahahahha
What is exchanged between the system and the surroundings
Answer:
see note under explanation
Explanation:
When describing system and surroundings the system is typically defined as the 'object of interest' being studied and surroundings 'everything else'. In thermodynamics heat flow is typically defined as endothermic or exothermic. However, one should realize that the terms endothermic and exothermic are in reference to the 'system' or object of interest being studied. For example if heat is transferred from a warm object to a cooler object it is imperative that the system be defined 1st. So, with that, assume the system is a warm metal cylinder being added into cooler water. When describing heat flow then the process is exothermic with respect to the metal cylinder (the system) but endothermic to the water and surroundings (everything else).
A mixture of0.159 moles of C is reacted with 0.117 moles of O2 in a sealed, 10.0 L-vessel at 500.0 K, producing a mixture of CO and CO2. The limiting reagent of the below reaction is carbon. For 0.159 moles of carbon, determine the amounts of products (both the CO and CO2) formed in this reaction. Also, determine the amount of O2 remaining and the mole fraction of CO when the reaction is complete.
3C(s)+2O2(g)â2CO(g)+CO2(g).Â
Answer:
Explanation:
The balanced chemical equation of this reaction;
[tex]3C_{(s)} + 2O_2{(g)} \to 2CO_{(g)}+CO_{2(g)} --- (1)[/tex]
Using the Stochiometric ratio of ratio; the product formed will be aligned with the stoichiometric ratio limiting reagent.
Thus, 3 moles of C yields 1 mole of [tex]CO_2[/tex] and 2 moles of CO.
Therefore;
1 mole of C yields 1/3 moles of [tex]CO_2[/tex] and 2/3 moles of CO
0.147 moles of C yields[tex]\dfrac{1 \times 0.159}{3}[/tex] moles of [tex]CO_2[/tex] and[tex]\dfrac{2}{3} \times 0.159[/tex] moles of CO
= 0.053 moles of [tex]CO_2[/tex] and 0.106 moles of CO
Also;
From the above reaction;
3 moles C reacts with 2 moles of [tex]O_2[/tex]
1 mole of C reacts with [tex]\dfrac{2}{3}[/tex] moles of [tex]O_2[/tex]
0.159 moles of C react with [tex]\dfrac{2}{3} \times 0.159[/tex] moles of [tex]O_2[/tex]
= 0.106 moles of [tex]O_2[/tex]
The remaining amount of [tex]O_2[/tex] = (0.117 - 0.106) mol
= 0.011 mol
The mixture comprises of the following after the reaction;
= 0.011 mol excess [tex]O_2[/tex] + 0.053 moles of [tex]CO_2[/tex] + 0.106 mol CO
= 0.17 moles of gas
Thus; moles fraction of CO is;
[tex]= \dfrac{ moles \ of \ CO \ in \ mixture }{total \ moles \ of \ gas \ in \ mixture}[/tex]
[tex]= \dfrac{0.106}{0.17}[/tex]
= 0.624
Dust and particulates released in the home may cause
Lung cancer
Increased allergies and respiratory problems
Nausea
Answer:
b) increased allergies and respiratory problems.
Explanation:
i hope this helps!
have a great rest of your day!
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Answer:
Human health effects of dust relate mainly to the size of dust particles. Dust may contain microscopic solids or liquid droplets that are small enough to get deep into the lungs and cause serious health problems. Large particles may irritate the nose, throat and eyes. ... Dust from soil can irritate the respiratory tract.
b. increased allergies and respiratory problems