CaCl2 is a(n)

A. None of these
B. Metallic compound
C. Covalent compound
D. Ionic compound

Answer:

See explanation

Explanation:

An electrolytic cell functions by a non spontaneous chemical process. Energy is supplied in the form of electricity through a battery to drive the electrochemical process.

A voltaic cell functions by a spontaneous chemical process. Energy or work can be derived from a voltaic cell.

When iron is rusting, a natural voltaic cell is set and the iron is converted to hydrated iron III hydroxide. The set up used for the extraction of sodium metal from brine functions on the basis of electrolysis.

Answer:

Todas son correctas

Explanation:

I) Los compuestos del carbono son solubles en disolventes no polares como el hexano, benceno, éter, etc. VERDADERO. La mayoría de los compuestos de carbono son apolares, y basados en la regla: Similar disuelve similar, podemos presumir que la mayoría de compuestos de carbono se disuelven en solventes no polares.

II) Los compuestos del carbono generalmente presentan puntos de fusión y de ebullición bajos. VERDADERO. Al ser sustancias apolares, sus fuerzas electrostáticas son bajas. De la misma manera, como su masa atómica es pequeña, las fuerzas de Van der Waals son despreciables haciendo que sus puntos de fusión y ebullición sean bajos respecto a sustancias de estrucutra similar.

III) La gran mayoría de los compuestos del carbono son combustibles, sean estos, gaseosos, líquidos o sólidos. VERDADERO. Los gases (Como el gas natural) son combustibles usados para cocina. Los líquidos (Como la gasolina) son combustibles y bastante inflamables. Los sólidos (Como la madera) se usan como combustibles para hacer asados o son el combustible en incendios forestales.

IV) El enlace covalente es característico de los compuestos del carbono. VERDADERO. La polaridad del carbono es neutral haciendo que la mayoría de los enlaces que forma sean covalentes.

Answer:

The kinetic energy of the electron just before the collision is 9.3 eV.

Explanation:

We can find the kinetic energy of the electron before the collision can be found by energy conservation:

[tex] E_{i} = E_{f} [/tex]

[tex] K_{a_{i}} + K_{e_{i}} = K_{a_{f}} + K_{e_{f}} [/tex]   (1)

Where:

[tex]K_{a_{i}}[/tex]: is the initial kinetic energy of the atom

[tex]K_{a_{f}}[/tex]: is the final kinetic energy of the atom = 6.1 eV + [tex]K_{a_{i}}[/tex]

[tex]K_{e_{i}}[/tex]: is the initial kinetic energy of the electron =?

[tex]K_{e_{f}}[/tex]: is the final kinetic energy of the electron = 3.2 eV

By solving equation (1) for [tex]K_{e_{i}}[/tex] we have:

[tex]K_{a_{i}} + K_{e_{i}} = (6.1 eV + K_{a_{i}}) + 3.2 eV[/tex]

[tex] K_{e_{i}} = 6.1 eV + 3.2 eV = 9.3 eV [/tex]

Therefore, the kinetic energy of the electron just before the collision is 9.3 eV.

I hope it helps you!

Answer: A hygroscopic substance is one that readily attracts water from its surroundings, through either absorption or adsorption

Explanation:

Answer:

Explanation:

Overuse of antibiotics leads to bacteria's resistance against our drugs. This is increasing at an alarming rate and the reason is that overuse of antibiotics kills bacteria that lack the "resistance" gene or gene that can help them survive the antibiotics (similar is the case for insects that die to insecticides). But, some bacteria can have random mutations in their gene that can help them survive the antibiotic (similar is the case for some insects that can survive the insecticide), thus the surviving bacteria give rise to next generation of bacteria that are resistant to the given antibiotic (similar to how insects that survive the insecticide give birth to new insects that are resistant to insecticide too). Soon, every generation adds new antibiotic resistant bacteria (or new insecticide resistant insects in the case of insects) which is dangerous for all of life on this planet. Therefore, both are similar in the sense that new generations of these organisms will be resistant to our weapons against them.

Answer:

c. Looking for improvements

Explanation:

I took the quiz and it was right

Answer: C

Explanation:

just took the test

Answer:

1.2 × 10³ L

Explanation:

Step 1: Calculate the total number of gaseous moles

n = nH₂ + nCl₂ = 100 mol + 100 mol = 200 mol

Step 2: Convert 30 °C to Kelvin

We will use the following expression.

K = °C + 273.15 = 30 + 273.15 = 303 K

Step 3: Calculate the volume of the container

We will use the ideal gas equation.

P × V = n × R × T

V = n × R × T / P

V = 200 mol × (0.0821 atm.L/mol.K) × 303 K / 4 atm = 1.2 × 10³ L

Answer:

inhibitor :)

Explanation:

Catalysts speed the reaction up, and the other 2 are essential for the reaction to work, so an inhibitor :)

Answer:

Inhibitor

Explanation:

Answer:

51.6058

Explanation:

The percentage of abundance is changed to decimal by dividing 100

Answer:

An example of a chemical property of iron would be that it is capable of combining with oxygen to form iron oxide, or rust.

Explanation:

You have no choice listed, so I provided an example.

Answer:

carbon

Explanation:

because it is an allotrope of carbon

Answer:

Carbon

Explanation:

its literaly carbon

Answer:

D. 2

Explanation:

On the right side of the equation:

Al has 1, Zn has 3, NO3 has 6

But on the left side:

Al has 1, Zn has 1, NO3 has 3

1. So, if we add a coefficient of 2 to Al(NO3)3, then NO3 now has 6-which is what it needs.

2. But now the Al on the right side of the equation is not balanced, so give it a coefficient of 2.

3. To make the Zn balance, just add a coefficient of 3 on the left side of the equation.

Which leaves us with:

2Al + 3Zn(NO3)2 --> 2Al(NO3)3 + 3Zn

And now there are the same number of each compound on both sides of the equation.

Good luck! If you have any questions on this answer leave a comment :)

The question is incomplete as the measured value isn't given. However, an hypothesized measured value will be used to explain how to calculate the percentage error.

Answer:

2.5%

Explanation:

Percentage error :

[(measured value - True value)/ True value] * 100%

The measured value is the value obtained during an while using a measuring device.

If the measured value is = 0.123

Then, the percent error will be :

[(0.123 - 0.120) / 0.120] * 100%

(0.003 / 0.120) * 100%

0.025 * 100%

= 2.5%

The percent error is 2.5%. When the true value was 0.120.

Percent error is a measurement used to quantify the discrepancy between an estimated or experimental value and a known or accepted value.

Given information:

The measured value is 0.123

The true value is 0.120

Calculate the percent error using the formula given as below:

Percent Error = (|True Value - Measured Value| / True Value) * 100%

Substituting the given values in the above equation:

Percent Error = (|0.120 - 0.123| / 0.120) × 100%

= (0.003 / 0.120) × 100%

= 0.025 × 100%

= 2.5%

Therefore, the percent error is 2.5%.

To learn more about the percent error, follow the link:

https://brainly.com/question/3105259

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Your question is incomplete, the complete question was:

The true value was 0.120 and the measured value is 0.123. What was your percent error?

Answer:

8.3 × 10³ mL

Explanation:

Step 1: Calculate the mass of water that contains 100 mg of Pb

The concentration of Pb in the sample is 0.0012% by mass, that is, there are 0.0012 g of Pb every 100 g of water. The mass of water that contains 100 mg (0.100 g) of Pb is:

0.100 g Pb × 100 g Water/0.0012 g Pb = 8.3 × 10³ g Water

Step 2: Calculate the volume corresponding to 8.3 × 10³ g of water

Since the solution is diluted, we will assume the density of the sample is equal than the density of water (1 g/mL).

8.3 × 10³ g × 1 mL/1 g = 8.3 × 10³ mL

The volume of the water in milliliters contains 100 mg of Pb is;

V =  8.3 × 10³ mL

We are given the concentration of Pb in the sample as 0.0012% by mass.

That means that there are 0.0012 g of Pb in every 100 g of water.

Thus, the mass of water that contains 100 mg (0.100 g) of Pb is calculated as;

(0.100 g Pb × 100 g of Water)/0.0012 g of Pb = 8.3 × 10³ g of Water

Now, we know that the density of water (1 g/mL) but we are not given the density of the sample.

Thus, since the solution is diluted we can equally say that;

Density of sample = 1 g/mL

Formula for Volume is;

V = mass/density

Thus;

V = 8.3 × 10³ g/1 g/mL

V = 8.3 × 10³ mL

Read more about Volume of solution at; https://brainly.com/question/17055828

Answer:

1) The percentage of oxygen in dry air is _______

C. 21

2) The composition of the Earth’s earliest atmosphere was different to that of the present atmosphere. Which of these gases was present in large amounts in the Earth’s earliest atmosphere?

B. CARBON DIOXIDE

Hope it helps

have a nice day

Answer: The percentage of oxygen in dry air is .  21

Explanation:  Ammonia gases was present in large amounts  in the easth7s earliest atmosphere

Hope it will help you

Answer:

Average velocity of car = 50 km/h

Explanation:

Given information;

Distance cover by man in his car = 25 kilometer

Time taken by man to cover distance = 30 min

Find:

Average velocity of car

Computation:

Time taken by man to cover distance = 30 min

Time taken by man to cover distance = 30 / 60

Time taken by man to cover distance = 0.5 hour

Average velocity = Distance / Time

Average velocity of car = Distance cover by man in his car / Time taken by man to cover distance

Average velocity of car = 25 / 0.5

Average velocity of car = 50 km/h

Answer:

Potassium

Explanation:

To solve this question we need to find, as first, the average atomic mass of the element knowing that is defined as the sum of the masses of each isotope times their abundances. For the element X:

Average atomic mass:

38*0.0967 + 39*0.7868 + 40*0.1134 + 41*0.0031

= 39.02g/mol

The atom that has the average atomic mass closest to 39.02g/mol is Potassium, K = 39.10g/mol.

Hi there!

[tex]\large\boxed{3.203 * 10^{22} atoms}[/tex]

We can use the following conversions to solve:

Total mass --> amount of mols --> amount of atoms (Avogadro's number)

Begin by calculating the amount of boron trifluoride in 3.61 grams:

3.61 g * (1 mol BF₃ / 67.8 g) ≈ 0.0532 mol BF₃

Use avogadro's number to convert:

0.0532 mol * 6.02× 10²³atoms / 1 mol = 3.203 × 10²² atoms

Answer:

C thermal

Explanation:

Answer:

3.90g/mL

Explanation:

To find the density of a substance, divide the mass by the volume.

So, 37.6 / 9.65 = 3.89637

then round to 3 significant figures

Good luck!

Answer: the equation for the reaction is NH4Cl (s) --> NH3 (g) + HCl (g)

equation for heat reaction:

ΔH25° = (ΔH25° NH3 + ΔH25° HCl) - ΔH25° NH4Cl)

question 2:

the 1st and 3rd reactions are better ontained through  refrence sources and the 2nd and 4th are the easiest and safest to measure in the laboratory. The 1st and rd reaction contains noxious gases this is because there is a (g) in both of the reactions. And the 2nd and 4th does NOT contain noxious gases so i assume its the safest to measure out in the lab  

Answer:

[tex]\boxed {\boxed {\sf 0.601 \ g \ As}}[/tex]

Explanation:

We want to convert atoms of arsenic to mass in grams. We have to complete 3 steps.

The first step is converting atoms to moles. We use Avogadro's Number for this. This number is 6.022*10²³ and it is the number of representative units (molecules, atoms, etc.) in 1 mole of a substance. In this problem, the particles are atoms of arsenic. So, 1 mole of arsenic contains  6.022*10²³ atoms of arsenic. Use this information to make a ratio.

[tex]\frac{1 \ mol \ As}{{6.022*10^{23} \ atoms \ As} }[/tex]

Multiply by the number of atoms provided in the problem: 4.83 × 10²¹

[tex]4.83 *10^{21} \ atoms \ As *\frac{1 \ mol \ As}{{6.022*10^{23} \ atoms \ As} }[/tex]

The units of atoms of arsenic (atoms As) cancel.

[tex]4.83 *10^{21} *\frac{1 \ mol \ As}{{6.022*10^{23}} }[/tex]

Condense into 1 fraction.

[tex]\frac{4.83 *10^{21} }{{6.022*10^{23}} } \ mol \ As[/tex]

[tex]0.008020591166 \ mol \ As[/tex]

The next step is converting moles to grams. We use the molar mass for this, which is provided. There are 74.92 grams of arsenic in 1 mole of arsenic, so we can make another ratio.

[tex]\frac {74.92 \ g\ As}{ 1 \ mol \ As}[/tex]

Multiply by the number of moles we calculated.

[tex]0.008020591166 \ mol \ As*\frac {74.92 \ g\ As}{ 1 \ mol \ As}[/tex]

The units of moles of arsenic (mol As) cancel.

[tex]0.008020591166 *\frac {74.92 \ g\ As}{ 1}[/tex]

[tex]0.6009026901 \ g \ As[/tex]

The original measurement of atoms (4.83 × 10²¹ ) has 3 significant figures, so our answer must have the same.

For the number we calculated, that is the thousandth place. The 9 in the ten-thousandth place (0.6009026901) tells us to round the 0 to a 1.

[tex]0.601 \ g \ As[/tex]

There are approximately 0.601 grams of arsenic.

Answer:

Synthetic sponges are made of three basic ingredients: cellulose derived from wood pulp, sodium sulphate, and hemp fiber. Other materials needed are chemical softeners, which break the cellulose down into the proper consistency, bleach, and dye.

Explanation:

IDK, BUT HOPE IT HELPS?

Answer:

4.. increases

5..lowers

6.. increases

7.. increases

8.. speed

Answer:

When a substance is heated, its temperature rises because its molecules move faster and gain thermal energy. Temperature measures the "hotness" or "coldness" of an object. The term heat refers to thermal energy being transferred from a hotter system to a cooler one.

Answer:

A

Explanation: