please help i don’t know this:(

Answer:

I think 2.6 sorry if its wrong

The number of moles of 18.3 grams of lithium is equal to 2.62 mol.

A mole can be defined as a metric unit that is used to evaluate a count of particles in the sample of a given substance. The particles counted are generally identical chemical entities, but they are individually distinct.

A mole is used for a large number of quantities of molecules, atoms, ions, or other specific particles. The number of chemical compounds or elements can be measured in the terms of moles.

The number of units of the chemical which are present in 1 mole is equal to 6.023 × 10 ²³  refers to Avogadro’s constant.

Given, the mass of lithium in the sample = 18.2 g

The mass of one mole of lithium = 6.94 g

6.94 grams of lithium has moles = 1 mol

18.2 g of lithium has moles of Li = 18.2/6.94 = 2.62 mol

Therefore, the moles in 18.2 g of Lithium is 2.62 mol.

Learn more about the mole, here:

brainly.com/question/26416088

#SPJ2

FeCl2 + Na2CO3 = FeCO3 + 2NaCl

Answer:

0.703g Na must reacted

Explanation:

The reaction of Sodium, Na, With water, H₂O is:

2Na(s) + 2H₂O(l) → 2NaOH(aq) + H₂(g)

Where 2 moles of sodium reacts with an excess of water to produce 1 mole of hydrogen

To solve this question we have to use PV = nTR to solve the moles of the gas. With the moles of hydrogen we can find the moles of sodium that reacted and its mass:

Moles H₂:

PV = nRT

PV /RT = n

Where P is pressure = 1.15atm

V is volume in liters = 0.325L

R is gas constant = 0.082atmL/molK

T is absolute temperature = 25°C + 273 = 298.0K

1.15atm*0.325L / 0.082atmL/molK*298.0K = n

0.0153 moles of hydrogen are produced

Moles Na:

0.0153 moles H₂ * (2moles Na / 1mol H₂) = 0.0306 moles Na

Mass Na -Molar mass: 22.99g/mol-:

0.0306 moles Na * (22.99g / mol) =

Answer:

a. True

Explanation:

Distillation process is a process that is used to separate the components or the substances from the liquid mixtures by using selectively boiling and condensation.

While fractional precipitation is a process which separates the ions from solution based on the different solubilities.

Therefore, the answer is true.

Answer:

73.33% is the percent yield

Explanation:

Percent yield is defined as:

Actual yield (4.883g) / Theoretical yield * 100

Based on the reaction:

Cu(NO₃)₂(aq) + K₂CO₃(aq) → CuCO₃(s) + 2KNO₃(aq)

1 mole of copper nitrate reacts per mol of potassium carbonate.

To solve this question we must find limiting reactant. With limiting reactant we can find the theoretical moles of solid produced and its mass as follows:

Moles Cu(NO₃)₂:

0.1639L * (0.329mol / L) = 0.0539 moles

Moles K₂CO₃:

0.1639L * (0.528mol / L) = 0.0865 moles

As the reaction is 1:1, the limiting reactant is Cu(NO₃)₂.

1 mol of Cu(NO₃)₂ produces 1 mol of CuCO₃. That means theoretical moles produced are 0.0539 moles. And the mass is:

Mass CuCO₃ -Molar mass: 123.55g/mol-

0.0539 moles * (123.55g / mol) = 6.659g of CuCO₃ is the theoretical mass

And percent yield:

4.883g / 6.659g * 100

Answer:

aerosols

Explanation:

An ideal gas is one that follows the gas laws at all conditions of temperature and pressure. To do so, the gas would need to completely abide by the kinetic-molecular theory. On the other hand, a real gas is a gas that does not behave according to the assumptions of the kinetic-molecular theory.

Furthermore, the particles of an ideal gas are extremely small and have a mass equivalent to practically zero. Ideal gas particles also have no volume.

An example of a real gas is helium, oxygen, and nitrogen.

Answer:

Option A

Explanation:

Addition of too much of solvent will make the solution dilute due to which the crystals will not form. Hence option D is incorrect

On the other hand adding a minimum amount of boiling solvent will give a saturated solution for recrystallization. Hence, option A is incorrect

Addition of cold solvent will lower the rate of formation of crystals. Hence, both option B and C are incorrect

Answer:

Number of moles of photons required = 5.04 × 10⁴ moles

Explanation:

The energy of a photon can be calculated from Planck's equation E = hc/λ

Where h = 6.63 × 10-³⁴ Js and c, the velocity of light = 3.0 × 10⁸ m/s

Energy of one mole of photons = N₀ × hc/λ

wavelength of photon, λ = 520 nm = 5.20 × 10-⁷ m

Energy of one mole of photons = 6.02 × 10²³ × 6.63 × 10−³⁴ × 3 × 10⁸/5.20 × 10-⁷

Energy of one mole of photons = 2.30 × 10⁵ J/mol

Energy required to raise the temperature of a given mass of a substance, E = mcΔT

Where m is mass of substance,  c is specific heat capacity,  ΔT is temperature difference

Mass ofnwternin the pool = volume × density

Volume of water = Volume of swimming pool

Volume of water = 16 × 34 × 6 ft³ = 3264 ft³

1 ft³ = 28316.8 cm³; 3264 ft³ = 28316.8 × 3264 = 92426035.2 cm³

Density of water = 1 g/cm³

Mass of water = 92426035.2 cm³ × 1 g/cm³ = 92426035.2g

ΔT = 80°C - 50°C = 30°C, c = 4.18 J/g/K

Energy required to raise 92426035.2 g water by 30° C = 92426035.2 × 4.18 × 30

Energy required = 1.16 × 10¹⁰ J

Hence, number of moles of photons required = 1.16 × 10¹⁰ J/2.30 × 10⁵ J/mol

Number of moles of photons required = 5.04 × 10⁴ moles

Answer:

In a physical change the appearance or form of the matter changes but the kind of matter in the substance does not. However in a chemical change, the kind of matter changes and at least one new substance with new properties is formed.

Explanation:

hope it helps you

have a good day please mark me as brain list ☺️ sorry for picture

Answer: D. 48.75

Explanation: just took the test

Answer:

D

Explanation:

I got this question right on my test.

Answer:

63.7 °C

Explanation:

Step 1: Given and required data

Step 2: Calculate the final temperature of the water (T₂)

We will use the following expression.

Q = c × m × (T₂ - T₁)

T₂ = Q/c × m + T₁

T₂ = 3.85 × 10³ cal/(1 cal/g.°C) × 75.4 g + 12.6 °C = 63.7 °C

Answer: B.) Object X Is A Conductor

Explanation: Since object X was able to lose all of its charge by being grounded, this means that its charges were able to move about freely. This strongly suggests that object X is a conductor. If object X had been an insulator, the ground would have had virtually no effect on its net charge.

Answer:

hi

Explanation:

I'm just figuring this out

Answer:

12

Explanation:

because that plot and the iron

Answer:

Static energy is an energy between two charges.

Explanation:

a). A van de Graff generator builds up a positive electric charge on the dome by separating the negative static electric charges from the positive static charge using a quickly moving belt. The positive charge collects on the large metal dome of the generator. When the charge builds up is large enough, a lighting like spark can shoot from the dome to a grounded discharge rod.

             Like electric charges always repel each other, and oppositely electric charges will attract each other. When the aluminum pans are being charged by the van de Graff generator, then each of them attain the same positive polarity similar with the dome. Thus,  positive charge starts to accumulate over the surface of each of the pie pan. Each aluminum pan repels the others. These repulsive forces between the pans are so strong that they succeed in overcoming the gravity force and thus the top of the pan is pushed away from the generator's dome.

b). Static electricity is produced by a concentration of negative and positive electric charges. Like charges pushes away each other while unlike charges pulls each other.

            Objects generally have same numbers of positive charges as well as negative charges. And if there is any small imbalance in numbers of the charges on the object, it is charged.

            Negative charges easily torn away from the materials like the fur or hair. Also, the negative charges are held on other materials like the plastics. If we rub a plastic rod with fur, the negative charges will get transferred from fur to rod. The rod gets negatively charged and the fur is positively charged. As a result, the rabbit fur and the plastic rod were attracted to each other.

c). Coulomb's law stated that :

  [tex]$F=\frac{KQ_1Q_2}{d^2}$[/tex]    .............(i)

where, [tex]$Q_1$[/tex]  and [tex]$Q_2$[/tex] are the charges of two objects d is the distance between two objects.

As from the above equation, we can say that force of electrical attraction between two objects depends on the charges and the distance between objects.

1. The electrical force between two charged object is inversely proportional to the distance of separation between two objects.

Decreasing separation distance (d) between the objects will increase its attraction force.

2. And, increasing the charges of two objects(+ve and -ve) increases the force of attraction between two objects.

Answer: c????????

Explanation:

Answer:

[tex]\boxed {\boxed {\sf 836.8 \ Joules \ lost}}[/tex]

Explanation:

Since we are given the mass and change in temperature, we should use the following formula for heat.

[tex]q= mc \Delta T[/tex]

In this formula, m is the mass, c is the specific heat capacity, and ΔT is the change in temperature.

We know the mass of the water is 10 grams. We will have to look up water's specific heat, because it is not given. It is 4.184 J/g °C.

Let's find the change in temperature. This is the difference of the final and initial temperature. The water started at 80 °C and cooled to 60°C.

Now we have values for each variable.

Substitute the values into the formula.

[tex]q= 10 \ g * 4.184 \ J/g \textdegree C * -20 \textdegree C[/tex]

Multiply the first 2 numbers. The units of grams will cancel each other out.

[tex]q= 41.84 \ J/ \textdegree C * -20 \textdegree C[/tex]

Multiply again. This time, the degrees Celsius cancel.

[tex]q= -836.8 \ J[/tex]

A total of 836.8 Joules are lost.

Answer:

CERES is the latgest in the solar system

Explanation:

Answer:

186.3g

Explanation:

4.5moles of K₂CO₃  is in 1000ml

? moles of K₂CO₃ is in 300 ml

(4.5 × 300)/ 1000 = 1.35 moles of K₂CO₃

1 mole of K₂CO₃ = (39 × 2) + 12 + (16 × 3) = 78 + 12 + 48 = 138g

1.35 moles of K₂CO₃  = ?

= (1.35 × 138)/1 = 186.3g

Answer:

P-block

Explanation:

Chlorine

Atomic number (Z) 17

Group group 17 (halogens)

Period period 3

Block p-block

Answer:

What does "in which block does chlorine lies"? That question has no way to answer it because there is no question content lol

Explanation:

Answer:

[tex]m_{Pb(NO_3)_2}^{leftover}=38.34g[/tex]

Explanation:

Hello there!

In this case, given the chemical reaction by which the sodium chloride reacts with lead (II) nitrate and the former is the limiting reactant, it is possible to calculate the mass of lead (II) nitrate that are actually consumed according to the 2:1 mole ratio between them:

[tex]m_{Pb(NO_3)_2}=15.3gNaCl*\frac{1molNaCl}{58.44gNaCl}*\frac{1molPb(NO_3)_2}{2molNaCl} *\frac{331.21gPb(NO_3)_2}{1molPb(NO_3)_2} \\\\m_{Pb(NO_3)_2}=43.36gPb(NO_3)_2[/tex]

Thus, the leftover of lead (II) nitrate is:

[tex]m_{Pb(NO_3)_2}^{leftover}=81.70g-43.36g\\\\m_{Pb(NO_3)_2}^{leftover}=38.34g[/tex]

Best regards!

Answer:

Disability insurance is financial protection for your most valuable asset — the ability to work and earn an income. So why is it so commonly overlooked and misunderstood?

Homeowners insurance protects where you live. Car insurance protects what you drive. Health insurance protects your well-being.

But what protects your ability to work and earn an income? After all, that's what allows you to pay for all of the above.

To protect yourself against the risk of losing your paycheck due to injury or illness, there's disability insurance. In this article, we cover everything you need to know about this important, yet often overlooked type of insurance for your income.

Disability insurance definition

Disability insurance is a type of coverage that replaces a portion of your monthly income if injury or illness prevents you from working. It provides financial security for you and any loved ones who may depend on your most valuable asset — your ability to earn a paycheck. You may also hear disability insurance referred to as disability income insurance or income protection.

Explanation:

Answer:

Advantage: Hydropower is a fueled by water, so it's a clean fuel source.

Advantage: It is a domestic source of energy in the US.

Disadvantage: Fish populations can be impacted if fish cannot migrate upstream past impoundment dams to spawning grounds or if they cannot migrate downstream to the ocean.

Disadvantage: Hydropower plants can be impacted by drought. When water is not available, the  hydropower plants can't produce electricity.

Explanation:

Answer:

c

Explanation:

Answer:  dispersion forces, dipole-dipole and hydrogen bonds

Explanation:

Explanation:

NiCl2 + KOH = NiOH + KCl

since nickel is the primary element in nickel ii chloride, find the oxidation no of nickel in the compound and chlorine should have 2 as a subscription since the ii in the compound represents that nickel has an oxidation no of 2