[tex]\qquad \qquad \huge \pink {\sf{☁Answer☁}} \\ \\ [/tex]
falseAtoms are most stable when their outer shells are fulfilled or half-filled.[tex]\sf{\:мѕнαcкεя\: ♪...}[/tex]
Write a net ionic equation for the reaction that occurs when excess hydroiodic acid and chromium(II) carbonate (s) are combined.
Step 1: Write the balanced "molecular equation:
[tex]2HI(aq) + CrCO₃ (s) → CrI₂ (s) + H₂O(l) + CO₂(g)[/tex]
Step 2: Carbon dioxide and water are written in molecular form. Consult the solubility and net ionic equation rules on the information page to determine which of the other substances will dissociate:
[tex]2HI(aq) + CrCo₃ (s) → Crl₂ (s) +H₂O(l)+CO₂(g)[/tex]
yes no yes
Step 3: Dissociate all soluble salts, strong acids, and strong bases (except calcium hydroxide), Leave together all "not soluble" salts and weak acids or bases:
[tex] {2H₂O}^{ + } (aq) + {2I}^{ - } (aq) + CrCO₃ (s)→ {Cr}^{2 + } (aq) + {2I}^{ - }(aq) + 3H₂O(l) + CO₂(g)[/tex]
Step 4: Cross out "spectator lons that appear on both sides of the reaction (these lons do not participate in the chemistry) and rewrite the "net" reaction using the smallest possible coefficients:
[tex] {2H₂O}^{ + } (aq) + CrCO₃ (s) →3H₂O + CO₂ + {Cr}^{2 + } [/tex]
Oleic acid, a component of olive oil, is 76.54% C, 12.13% H, and 11.33% 0. The
experimental value of the molar mass is 282 g/mol.
a. What is the molecular formula of oleic acid?
b. If oleic acid has a density of 0.895 g/mL, how many molecules of oleic acid
are in 3.00 mL of oleic acid?
Answer:
a) The molecular formula of oleic acid is: [tex]C_{18}H_{34}O_{2}[/tex]
b) There are 5.74 x 10^21 molecules of oleic acid in a 3.00 mL sample.
Explanation:
a)
First, let's determine the empirical formula of oleic acid from the percentage composition provided by the question:
- Assuming a 100g sample of oleic acid, the correspondent mass of C, H and O would be:
mass of C = 76.54g
mass of H = 12.13g
mass of O = 11.33g
- We must determine the number of moles contained in each of the masses determined above. For that, let's use the atomic masses of C (12.01 u), H (1.007 u) and O (15.99 u) and the following equation:
[tex]number of moles = \frac{mass of sample}{molar mass}[/tex]
number of moles of C = 76.54g / 12.01 g/mol = 6.373 mol C
number of moles of H = 12.13g / 1.007 g/mol = 12.04 mol H
number of moles of O = 11.33g / 15.99 g/mol = 0.7086 mol O
- Next, we'll try to find whole-number ratios by dividing each number of moles obtained by the smallest value obtained (0.7086):
C = 6.373 / 0.7086 = 8.994 ≅ 9
H = 12.04 / 0.7086 = 16.99 ≅ 17
O = 0.7086 / 0.7086 = 1.000
- Now, we can write the empirical formula of oleic acid as: [tex]C_{9}H_{17}O[/tex]
Now that we have the empirical formula for oleic acid (C9H17O), let's check its molar mass and compare it to the experimental value provided by the question (282 g/mol):
molar mass (C9H17O) = 9 * 12.01 + 17 * 1.007 + 1 * 15.99 = 141.9 g/mol
Note that the molar mass obtained from the empirical formula (141.9 g/mol) and the experimental molar mass (282 g/mol) are different, thus we need to find an integer multiple to determine the molecular formula (keep in mind that molecular formulas always present kind and number of atoms of each element present in the molecular compound, while the empirical formula presents the smallest coefficients for each atom).
Molecular formula = n × Empirical formula
This integer multiple, n, can be obtained by dividing the molar mass, MM , of the compound by the empirical formula mass, EFM (the molar mass represented by the empirical formula):
n = MM / EFM
n = 282 / 141.9
n = 1.987 ≅ 2
Since the integer multiple is 2, we can multiply all coefficients in the empirical formula by 2 to find the molecular formula of oleic acid:
C9 H17 O x 2 = C18 H34 O2
Therefore, the molecular formula of oleic acid is: [tex]C_{18}H_{34}O_{2}[/tex]
b)
We need to calculate the amount of molecules of oleic acid in a 3.00mL sample, considering the density as 0.895 g/mL.
From the density provided, we can calculate the mass, in grams, of oleic acid contained in 3.00 mL of this compound:
1 mL ----------------------- 0.895 g oleic acid
3.00 mL ----------------- x
Solving for x, we have that there are 2.69 g of oleic acid in a 3.00 mL sample.
Next, considering the molar mass of oleic acid (282 g/mol), we can calculate the number of moles contained in 2.685g of the acid:
282 g -------------------- 1 mol oleic acid
2.69 g ----------------- y
Solving for y, we have that there are 0.00953 moles of oleic acid in a 3.00 mL sample.
Now, using the Avogadro's number (6.022 x 10^23 particles/mol), we can calculate the amount of molecules of oleic acid in the sample:
1 mol oleic acid ------------------------------- 6.022 x 10^23 molecules oleic acid
0.00953 mol oleic acid ------------------- z
Solving for z, we have that there are 5.74 x 10^21 molecules of oleic acid in a 3.00 mL sample.
If 25.0 mL of a 2.00 M HCl solution is diluted to 2.00 L, what is the molarity of the new solution?
The molarity of a new solution that has a volume of 25.0 mL of a 2.00 M HCl solution and diluted to 2.00 L is 0.025M.
How to calculate molarity of a solution?The molarity of a solution can be calculated using the following formula:
C1V1 = C2V2
Where;
C1 = initial concentrationC2 = final concentrationV1 = initial volumeV2 = final volume2 × 25 = 2000 × C2
50 = 2000C2
C2 = 50 ÷ 2000
C2 = 0.025M
Therefore, the molarity of a new solution that has a volume of 25.0 mL of a 2.00 M HCl solution and diluted to 2.00 L is 0.025M.
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Which of the following compounds will have the lowest molar solubility in pure water?
a-AgBrO3, Ksp = 5.38 x 10-5
b-MnCO3, Ksp = 2.24 x 10-11
c-Hgs, Ksp = 1.60 x 10-54
d-Zns, Ksp = 2.00 x 10-25
e-SrS04, Ksp = 3.44 x 10-7
Answer:
C
Explanation:
It has the lowest Ksp, so it will have the lowest Molar Solubility
Without conducting an experiment, how could you predict if a species in a solution is acidic or basic? Give some examples.
Without conducting an experiment, one can determine if a species in a solution is acidic or basic by using a litmus paper.
Litmus testAcidic species would turn a blue litmus paper to red but have no effects on red litmus paper.
Basic species would turn a red litmus paper to blues but have no effects on blue litmus paper.
Thus, in order to determine if a species in a solution is acidic or basic without conducting any experiment, dipping a litmus paper into the solution would give an indication.
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During complete metamorphosis, what best describes the transformation from a larva to a pupa?
The larva goes through a big change in color.
The larva might form a cocoon or a chrysalis.
The larva might hatch into an adult.
The larva sheds its skin several times.
Answer:The larva might form a cocoon or a chrysalis.
Explanation:
Which element has the highest 2nd ionization energy?
A. Be
B. C
C. Li
D. B
Answer:
The answer is c.........
What is the molarity of 4 g of NaCl in 3,800 mL of solution?
Answer:
.018 M
Explanation:
Mole weight of NaCl (from periodic chart) = 58.44 g /mole
4 g / 58.44 gm/mole = .06845 mole
.06845 mole / (3.8 liter ) = .018 M
activity acid bases solutions project need help !!!!
1. Acids have highest concentration of hydronium ions.
2. Bases have highest concentration of Hydroxide ions
3. a. less than 7 b. more than 7
4. Acids (Presence of hydronium ions)
You need Conclusions too?
Wildfires displace many animals and leave behind ash and soot-covered habitats for the animals that
survive. If a wildfire
occurred in the Everglades, which insect would be the
most likely to survive
predators in an ash and soot-covered habitat? (SC.5.L. 15.1)
A. Red dragonfly
B. Green grasshopper
C. Brightly colored butterfly
D. Gray-colored speckled moth
7. A group of students is using models to explore the relationship between the shape of a bird's beak
the type of food it eats. The students design an investigation using classroom items as beaks. Each
If a wildfire occurred in the Everglades, the insect which most likely to survive predator is gray-colored speckled moth.
What are predators?Predators are those animals which for their survival will hunt or kill another animals for the fulfilment of their food need.
If wildfire occured in the everglades region then the insect would be the most likely to survive predators in an ash and soot covered habitat is gray-colored speckled moth which is also known as darwin moth as it takes part in evolution of natural process.
Hnece the required animal is gray-colored speckled moth.
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Aerobic decomposition of organic matter requires
A.nitrogen.
B.oxygen.
C.carbon dioxide.
D.water.
Answer:
Option B: Oxygen.
Explanation:
Hope this helped.
Which of the following conversions is/are incorrect.
a.1 meter = 1000 millimeters
b.100 millimeters = 1 centimeter
c.500 centimeters = 0.5 meters
d. 1 kilometer = 1000 meters
C+A
B+ C
D+ C
A+B
Answer:
B + C ARE INCORRECT FROM THE ABOVE GIVEN CONVERSIONS.
Which chemical symbol describes an element? C2H6 Cl2 H2O2 CuSO4
Answer:
Cl2
Explanation:
Chlorine is a diatomic element so it is Cl 2
the others are MOLECULES (made up of atoms of ELEMENTS)
Ethanoic acid has a pKa of 4.75. Find the pH of the solutions that results from the addition of 40.0 mL of 0.040 M NaOH to 50.0 mL of 0.075 M ethanoic acid.
Answer:
About 4.63.
Explanation:
The reaction between ethanoic acid (CH₃COOH) and sodium hydroxide (NaOH) can be described by the following net ionic equation:
[tex]\displaystyle \text{CH$_3$COOH}_\text{(aq)} + \text{OH}^-_\text{(aq)}\longrightarrow \text{CH$_3$COO}^-_\text{(aq)} + \text{H$_2$O}_\text{($\ell$)}[/tex]
40.0 mL of 0.040 M NaOH contains:
[tex]\displaystyle 40.0\text{ mL} \cdot \frac{0.040\text{ mol NaOH}}{1000\text{ mL}} = 0.0016\text{ mol NaOH}[/tex]
Because NaOH is a strong base, it dissociates completely. Hence, the amount of OH⁻ present is 0.0016 mol. Na⁺ acts as a spectator ion.
50.0 mL of 0.075 M CH₃COOH contains:
[tex]\displaystyle 50.0\text{ mL} \cdot \frac{0.075\text{ mol CH$_3$COOH}}{1000\text{ mL}} = 0.0038\text{ mol CH$_3$COOH}[/tex]
OH⁻ is the limiting reagent of the reaction. Therefore, as the reaction proceeds to completion:
The amount of OH⁻ drops to 0 mol. The amount of CH₃COOH decreases to (0.0038 - 0.0016) mol = 0.0022 mol. And the amount of CH₃COO⁻ increases to (0 + 0.0016) mol = 0.0016 mol.Note that all species present are in a one-to-one ratio.
To find pH, we can use the Henderson-Hasselbalch equation:
[tex]\displaystyle \text{pH} = \text{p}K_a + \log\frac{[\text{Base}]}{[\text{Acid}]}[/tex]
The total volume of the solution is 40.0 mL + 50.0 mL = 90.0 mL.
Hence, find [CH₃COOH]:
[tex]\displaystyle \left[\text{CH$_3$COOH}\right] = \frac{0.0022\text{ mol}}{90.0\text{ mL}} \cdot \frac{1000\text{ mL}}{1\text{ L}} = 0.024\text{ L}[/tex]
Find [CH₃COO⁻]:
[tex]\displaystyle \left[\text{CH$_3$COO}^-\right] = \frac{0.0016\text{ mol}}{90.0\text{ mL}}\cdot \frac{1000\text{ mL}}{1\text{ L}} = 0.018\text{ M}[/tex]
Therefore, the pH of the resulting solution is:
[tex]\displaystyle \begin{aligned}\text{pH} & = \text{p}K_a + \log\frac{[\text{Base}]}{[\text{Acid}]} \\ \\ & = (4.75) + \log \frac{(0.018)}{(0.024)} \\ \\ & = 4.75 + (-0.12) \\ \\ & = 4.63\end{aligned}[/tex]
In conclusion, the pH of the resulting solution is about 4.63.
When 3.00 g of hydrogen reacts with 4.00 g of oxygen, 4.00 g of water is formed.
(a) What is the limiting reactant?
(b) What is the theoretical yield?
(c) What is the percent yield?
Question 11 options:
a)
(a) oxygen
(b) 4.51 g
(c) 88.7 %
b)
(a) hydrogen
(b) 4.51 g
(c) 88.7 %
c)
(a) oxygen
(b) 4.05 g
(c)13.0 %
d)
(a) hydrogen
(b) 4.05 g
(c) 13.0 %
Answer:
Answer A
Explanation:
2 H2 + O2 = 2 H2O
knowing the mole weights of these elements shows O2 is the limiting reactant in this situation.
4 g oxygen is 4 /31.998 = .125 mole O2
We should get two times these moles of water = .250 moles
weight = .250 (1.008 * 2 + 15.999) = 4.50 gm H20 (theoretical)
....but we only got 4 gm
4/4.50 = 88.8%
Where does runoff end up?
a)ponds
b)streams
c)rivers
d)all of the above
Answer:
All of the above :D
Explanation:
When rain falls, if it doesn't get absorbed by the dirt, it will go into streams, rivers, and ponds. That is actually how flooding is caused!!! :D
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How many molecules are there in a 42.3g sample of water
Answer:
This means that one mole of water molecules has a mass of 18.015g.
42.3g * 1 mole H2O/18.015g
= 2.3480 moles H2O
We are using the avogadros number to find the number of molecules of water
2.3480 H2O * 6.022*10^ 23moles/ 1mole of H2O
That's 2.3480 multiplied by 6.022*10^23 divided by 1 mole of H2O
Number of molecules = 1.4140 *10^24 molecules
what major organic product would you expect to obtain when acetic anhydride reacts with ch3ch2ch2oh nh3
The major product of the reaction between acetic anhydride and CH3CH2CH2OH is CH3COOCH2CH2CH3. While, the major product of the reaction between acetic anhydride and NH3 is CH3CONH2.
What is acetic anhydride?Acetic anhydride is the compound (CH3COO)2. It is a precursor for the synthesis of many organic compounds.
Now let us consider the use of acetic anhydride in synthesis. The major product of the reaction between acetic anhydride and CH3CH2CH2OH is CH3COOCH2CH2CH3. While, the major product of the reaction between acetic anhydride and NH3 is CH3CONH2.
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6.11C In 1976, the Viking I Lander was sent to Mars to analyze atmospheric gases and soil samples. The Viking I Lander was most likely a
a space probe.
b lunar module.
c space shuttle.
d natural satellite.
The picture shows the cubic unit cell of CaF2. How many Ca2+ ions and F- ions are present in the cubic unit cell?
The total number of Ca2+ ions and F- ions that are present in the cubic unit cell will be 4 and 8 respectively.
How to calculate the unit cell?From the complete information, the number of Ca2+ at corners will be (8 × 1/8 = 1) and those a the center will be (6 × 1/2 = 3). Therefore, the total number of Ca2+ will be:
= 1 + 3 = 4
The total number of F- ions will be:
= 4 × 2 = 8
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What type of microorganism turns milk into yogurt?
For yogurt production, probiotic bacteria and the Streptococcus thermophilus strain work together to produce a stable balance of bacteria in the culture.
What is the solubility of MgCO₃ in a solution that contains 0.080 M Mg²⁺ ions? (Ksp of MgCO₃ is 3.5 × 10⁻⁸)
Answer: 4.4 x 10^-7
Explanation:
The dissociation equation for this reaction is:
MgCO3 (s) → Mg+2 (aq) + CO3-2 (aq)
[tex]\text { So, } k_{s p}=(x+0.08) x[/tex] (Here 0.08 >>> x )
[tex]\begin{aligned}\Rightarrow 3.5 \times 10^{-8} &=0.08 \times x \\\Rightarrow x &=\frac{3.5}{0.08} \times 10^{-8} \\&=4.37 \times 10^{-7} \\\Rightarrow x & \approx 4.4 \times 10^{-7} \mathrm{~M}\end{aligned}[/tex]
So the solubility MgCO₃ in a solution that containing 0.080 M Mg²⁺ is 4.4 x 10^-7
Which of the following is an example of chemical weathering?
A. A river carrying dirt into a lake.
B. Wind carrying sand from a beach.
C. Chemicals in water dissolving minerals in rock.
D. Friction between two rock surfaces grinding away minerals.
Answer:
C
Explanation:
Answer: D. Friction between two rock surfaces grinding away minerals.
Explanation: chemical weathering involves erosion from rocks/materials
Step 1: Pick your favorite physical activity This can be almost anything! Try to pick an activity that you like to participate in, but you can pick anything you want. It could be hockey, tennis, wakeboarding, dancing, rock climbing, or even walking your dog! Almost ANY activity will work for this assignment. Step 2: Research the activity Get on the internet and learn about the activity you selected. Step 3: Write a brief report - 2 full paragraphs Be sure to include the following information in your report: - What activity you selected and why you selected it. - 2 health benefits of your activity. - 3 different muscles that your activity uses or "works out." - If participating in your activity presents any safety concerns. When you have finished your 2 full paragraphs, submit your assignment here!
Dancing is a physical activity which strengthens the abdominal and calf muscles as well as improves flexibility.
What is a physical activity?A physical activity is any activity which involves movement of the body in order to strengthen the muscles and to be physically fit.
Dancing is a physical activity which involves intricate and repeated movements of the body.
Dancing is beneficial because;
it helps to relieve stress it improves flexibility it builds muscle enduranceSome muscles involved in dancing include;
The abdominal muscles The quadricepsthe glutesSome risks in dancing include muscle injuries, dislocations and possibly fractures due to falls.
Therefore, a dancing routine strengthens the abdominal and calf muscles as well as improves flexibility.
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What is the molarity of a solution that has 175 g of LICI in 1085 mL of solution?
Answer:
3.8 M
Explanation:
Mole weight of LiCl = 6.94 + 35.45 = 42.39 ( from periodic table)
175 g of this is then 175 / 42.39 = 4.13 moles
4.13 moles / (1085/1000) = 3.8 M
A 25.0-L balloon at 20.0 ⁰C is placed in a hot water bath at 90 ⁰C. After 15 minutes, the volume of the balloon stops expanding. What is the new volume of the balloon?
Apply Charles law
V1T2=V2T125(90)=20V225(9)=2V2225=2V2V2=225/2V2=112.5LWhen fossil fuels are burned, they release pollutants into the air. When hydrogen is burned, it produces clean water. There are limited amounts of fossil fuels that can be uncovered by digging in the Earth. Hydrogen must be produced from other materials, such as water, which requires using energy.
In order to determine whether replacing fossil fuels with hydrogen would be good for the environment, what question must be answered?
Answer: can hydrogen produce as much energy as burning fossil fuels?
Explanation:
100 points! Please help if you are able to.
Here are the balanced equations
C_2H_5OH+3O_2--->2CO_2+3H_2O+Energy2AgCl-->2Ag+Cl_2AgNO_3+Zn--->Ag+ZnNO_33BaCl_2+Al_2(SO_4)_3--->3BaSO_4+2AlCl_3H_2+I_2--->2HIDone!
A student observes the phenomenon where a straw has a different appearance when placed in water. Once this was noted by the student, they then immediately thought about why they have been unable to successfully catch fish when spearing them in the water. Relate these two phenomenon and select ALL statements that apply to the phenomena described here.
A)The water distorts the image of the fish so that its image is inverted.
B)The student is not aiming correctly due to refraction of the fish in the water.
C)The water magnifies the image, making the target fish look bigger than it actually is.
D)The light waves travel at a different speed in water and make the fish appear farther away.
E)The diffraction of the light around objects flips the image from left to right, making aiming for fish more of a challenge.
Answers are B and D
Answer:
b, and d
Explanation:
if the student did not aim correctly, and for d if the light waves travelled differently
10 POINTS!
What stops beta particles?
skin
aluminum foil
paper
air
Answer:
The answer is aluminum foil.
Answer:
aluminum foil Mark me brainliest, please.