SOMEONE PLEASE HELPPP​

Answer:If you are sedentary (little or no exercise) : Calorie-Calculation = BMR x 1.2.

If you are lightly active (light exercise/sports 1-3 days/week) : Calorie-Calculation = BMR x 1.375.

Explanation:

Answer:

Amount of salt dissolved in each liter of seawater = 40 g

Explanation:

According to Archimedes principle, a body will float in a fluid if the upthrust experienced by a body is equal to the to the weight of the body.

Also, the volume of seawater displaced equals the volume of freshwater in the cup.

From the above principle, since the freshwater and cup floats in the seawater, their combined weight equals the upthrust.

Therefore, mass of equal volume of displaced seawater = mass of freshwater + mass of cup

Mass of freshwater = density of freshwater * volume

density of freshwater = 1 g/mL; volume = 375 mL

mass of freshwater = 375 mL * 1 g/mL = 375 g

mass of seawater = 375 + 15 = 390 g

mass of salt in 375 mL seawater = mass of seawater - mass of freshwater

mass of salt = (390 - 375) g = 15 g

Since 15 g of salt are dissolved in 375 mL seawater, mass of salt in 1 L of seawater =(1000 mL/ 375) * 15g = 40 g

Therefore, amount of salt dissolved in each liter of seawater = 40 g

Answer:

Wind, water, gravity, and ice

Explanation:

Water can erode soil material. Especially if the soil is bare, dry and erodible erosion via rain particles can occur. Wind is another factor that cause soil erosion. Dry soil particles( Especially if they are fine) can move to other areas if wind exists. Ice is another issue on erosion. Ice, when it is melting, can carry soil particles.

Answer: it is B

Explanation:

Answer:

175

Explanation:

Answer:S²⁻

Explanation:

Sulphur is in group 16. The atomic number of sulphur is 16.

However, sulphur can accept two electrons to form the sulphide ion S²⁻ which contains 18 electrons, hence the answer provided above.

Answer:

Chemical symbols refer to chemical elements only. They do not necessarily refer to atoms of that element, but also to ions.

Explanation:

Answer: d. the same electron configuration (isoelectronic) as neon.

Explanation:

Isoelectronic species are defined as the molecules which have the same number of electrons.

Atomic number of nitrogen is 7 and thus has 7 electrons. Nitrogen has electronic configuration of 2,5 and thus can gain 3 electrons and thus [tex]N^{3-}[/tex] will have electronic configuration of 2,8 ( same as that of neon)

Atomic number of oxygen is 8 and thus has 8 electrons. Oxygen has electronic configuration of 2,6 and thus can gain 2 electrons and thus [tex]O^{2-}[/tex] will have electronic configuration of 2,8 ( same as that of neon)

Atomic number of flourine is 9 and thus has 9 electrons. Flourine has electronic configuration of 2,7 and thus can gain 1 electron and thus [tex]F^{-}[/tex] will have electronic configuration of 2,8 ( same as that of neon)

Atomic number of sodium is 11 and thus has 11 electrons. Sodium has electronic configuration of 2,8,1 and thus can lose 1 electron and thus [tex]Na^{+}[/tex] will have electronic configuration of 2,8 ( same as that of neon)

Atomic number of magnesium is 12 and thus has 12 electrons. Magnesium has electronic configuration of 2,8,2 and thus can lose 2 electrons and thus [tex]Mg^{2+}[/tex] will have electronic configuration of 2,8 ( same as that of neon)

Atomic number of aluminium is 13 and thus has 13 electrons. Aluminium has electronic configuration of 2,8,3 and thus can lose 3 electrons and thus [tex]Al^{3+}[/tex] will have electronic configuration of 2,8 ( same as that of neon)

Answer:

From the given equation, we can see that for every 2 moles of Al, we get 3 moles of H2

So, we can say the the number of moles of H2 is 3/2 times the number of moles of Al

We are given the number of moles of Al and we have to find the number of moles of H2

We have deduced the relationship:

Moles of Al * 3 / 2 = Moles of H2

Replacing the variables with given values

3.5 * 3 / 2 = Moles of H2

Moles of H2 = 5.25 moles

Answer:

The mass of sodium chloride in the mixture is 18.75%

Explanation:

Here, we want to calculate the percentage of sodium chloride in the mixture.

The total mass of the mixture is 52 g + 12 g = 64 g

So the percentage mass of sodium chloride will be;

mass of sodium chloride/ Total mass * 100%

That will be: 12/64 * 100 = 18.75%

Answer:

atom

Explanation:

the atom is the smallest form.

Answer:

11.86%

Explanation:

First, we convert both solvent and solute to the same unit, say, kg. We have.

Mass of Sodium Bicarbonate = 7g = 7/1000 kg = 0.007 kg

Mass of water = 0.052 kg.

Formula for the mass percent is

% of sodium bicarbonate = [(mass of sodium bicarbonate) / (mass of total solution) * 100%]

Total mass of solution = 0.007 + 0.052 Total mass of solution = 0.059

% of sodium bicarbonate = 0.007 / 0.059 * 100%

% of sodium bicarbonate = 11.86%

Therefore, the mass percent of sodium bicarbonate I'm the solution is 11.86%

Answer:

Kps = 3.07 x 10⁻⁸

pKsp= 7.51

Explanation:

First, we calculate the molar solubility of  silver(I)phosphate (Ag₃PO₄) from the solubility in g/L by using its molar mass (418.6 g/mol):

2.43 g/L x 1 mol/418.6 g = 5.8 x 10⁻³ mol/L= s

Now, we have to write the ICE chart for the aqueous equilibrium of Ag₃PO₄ as follows:

     Ag₃PO₄(g) ⇄ 3 Ag⁺(aq) + PO₄³⁻

I                               0              0

C                            +3s           +s

E                            3s               s

Ksp = [Ag⁺]³[PO₄³⁻]= (3s)³s= 27s⁴

Since s=5.8 x 10⁻³ mol/L, we calculate Ksp:

Ksp= 27(5.8 x 10⁻³ mol/L)⁴= 3.07 x 10⁻⁸

The pKsp value is:

pKsp= - log Ksp = -log (3.07 x 10⁻⁸) = 7.51

Answer:

Explanation:

The percentage error of a certain measurement can be found by using the formula

[tex]P(\%) = \frac{error}{actual \: \: number} \times 100\% \\ [/tex]

From the question

actual mass = 200 g

error = 200 - 196.59 = 3.41

We have

[tex]p(\%) = \frac{3.41}{200} \times 100 \\ = 1.705[/tex]

We have the final answer as

Hope this helps you

17.5 grams of NaCl are needed to prepare 50.0 grams of a 35.0% salt solution.

What is Solution?

A solution is a homogenous mixture composed of two or more substances. In a solution, the components are evenly distributed throughout the mixture, resulting in a uniform appearance and properties.

The substance that is present in the largest amount is called the solvent, while the other substances present in lesser amounts are called solutes. When the solute dissolves in the solvent, the resulting mixture is called a solution.

To calculate the grams of NaCl needed to prepare a 35.0% salt solution, we can use the formula:

grams of NaCl = (percent salt / 100) x grams of solution

grams of NaCl = (35.0 / 100) x 50.0

grams of NaCl = 0.35 x 50.0

grams of NaCl = 17.5

Learn more about Solution from the given link

https://brainly.com/question/25326161

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Answer:

H2O

Explanation:

The equation for the decomposition of hydrogen peroxide is shown below;

2H2O2(l)-----> 2H2O(l) + O2(g)

Hence, the decomposition of H2O2 yields oxygen gas and water. Water is a non gaseous product of the reaction as clearly seen in the equation above.

Answer:

[tex]\%sand=25\%[/tex]

Explanation:

Hello.

In this case, given the mass of the mixture, we can define it in terms of the mass of sand and table salt as shown below:

[tex]m_{sand}+m_{salt}=20.00g[/tex]

Moreover, as after filtering, the mass of dry sand turns out 5.00 g, we can compute the % sand in the original mixture by dividing this value over the mass of the mixture as shown below:

[tex]\%sand=\frac{m_{sand}}{m_{mixture}}*100\%\\ \\\%sand=\frac{5.00g}{20.00g}* 100\%\\\\\%sand=25\%[/tex]

Best regards!

Answer: 600 mL

Explanation:

Given that;

M₁ = 5.85 m

M₂ = 1.95 m

V₁ = 200 mL

V₂ = ?

Now from the dilution law;

M₁V₁ = M₂V₂

so we substitute

5.85 × 200 = 1.95 × V₂

1170 = 1.95V₂

V₂ = 1170 / 1.95

V₂ = 600 mL

Therefore final volume is 600 mL

Answer:

true

Explanation:

hope it helps

Answer:

I'm pretty sure it's true

Explanation:

20 characters

Answer:

C. Milk boils at about 212F

Explanation:

The principal constituents of milk are water, fat, proteins, lactose (milk sugar) and minerals (salts). Milk also contains trace amounts of other substances such as pigments, enzymes, vitamins, phospholipids (substances with fatlike properties), and gases.

Answer:

1.45g of FeCl3

Explanation:

The equation of the reaction is given as;

2Fe + 3Cl2 --> 2FeCl3

2 mol of Fe reracts with 3 mol of Cl2 to form 2 mol of FeCl3

Upon converting to mass using;

Mass = Number of moles * Molar mass

( 2 * 55.85 = 111.7g ) of Fe reacts with ( 3 * 71 = 213g ) of Cl2 to form ( 2 * 162.2 = 324.4g) of FeCl3

Cl2 is the limiting reactant as it determines how much of FeCl3 is formed

213g of Cl2 = 324.4g of FeCl3

0.950g of Cl2 = x

x = (0.950 * 324.4 ) / 213

x = 1.45g of FeCl3

I'm not sure if this is the answer but maybe oil.

Answer:

B

Explanation:

Answer:

a) common ion effect

b) solubility

c) saturated solution

d) solubility product constant

e) molar solubility

Explanation:

When a substance, say BA2 is dissolved in a solution and another substance CA2 is dissolved in the same solution. The solubility of BA2 is decreased due to the addition of CA2. This is known as common ion effect.

The mass of a substance that will dissolve in a given Volume of solvent is known as it's solubility.

The molar solubility is the amount of moles of solvent that dissolves in 1 dm^3 of solvent.

A solution that contains just as much solute as it can normally hold at a given temperature is known as a saturated solution.

Lastly, the product of molar solubilites raised to the power of the molar coefficient is know as the solubility product constant.

The correct matches and their explanation are:

a) A decrease in the solubility of an ionic compound as a result of the addition of a common ion: Option 4. common ion effect

b) The mass of salt in grams that will dissolve in 100 mL of water: Option 1. solubility

c) A solution that has dissolved the maximum amount of a compound at a given temperature. Any further addition of salt will remain undissolved: Option 5. saturated solution

d)  The product of the molarities of the dissolved ions, raised to a power equal to the ion's coefficient in the balanced chemical equation: Option 3. solubility product constant

e) The maximum number of moles of a salt that will dissolve in 1 L of solution: Option 2. molar solubility

To learn more about molar solubility and common ion effect follow the link:

https://brainly.com/question/14782973

Answer:

Chromatography involves solvent separation on a solid medium.

Distillation takes advantage of differences in boiling points.

Evaporation removes a liquid from a solution to leave a solid material.

Filtration separates solids of different sizes.

Explanation:

Answer:

Its D) SO2

Explanation

Did the test

Answer:

1) No

2) The solvent contaminated the analyte

3) The solvent should be evaporated properly before washing and drying the analyte

Explanation:

During separation of organic compounds, solvents are used. These solvents are able to contaminate the analyte and lead to a large difference in melting point of solids obtained.

However, the error can be minimized by evaporating the solvent before washing, drying and melting point determination of the solid.

Answer:

41.7 kJ/mol

Explanation:

ln(k) = ln(A) − Eₐ/(RT)

Pick any two points.  I'll choose 100°C and 400°C.

When T = 100°C = 373 K, k = 1.10×10⁻⁹ L/mol s:

ln(1.10×10⁻⁹) = ln(A) − Eₐ/(R × 373)

When T = 400°C = 673 K, k = 4.40×10⁻⁷ L/mol s:

ln(4.40×10⁻⁷) = ln(A) − Eₐ/(R × 673)

Subtract the two equations and solve:

ln(4.40×10⁻⁷) −  ln(1.10×10⁻⁹) = -Eₐ/(R × 673) + Eₐ/(R × 373)

5.991 = 0.00120 Eₐ/R

Eₐ/R = 5013.4

Eₐ = 41700 J/mol

Eₐ = 41.7 kJ/mol