chemistry:

plz help me:D

Answer: c= 1.8 mol/l

Explanation: amount of substance remains same.

Amount of substance n = c1·V1 = c2·V2 and c1= c2·V2/ V1

Original concentration c1= 300 ml·0.750 mol/l / 125 ml

Answer: Burning fuels?

Explanation: I’m not very sure actually

Answer:

Cattles are giving nutrition supply throughout the year----some animals require nutrient enhancement for health

calves are given colostrum at birth----newborns require antibodies from their mothers

I dont want to write, so you know what the last option is

Explanation:

:) hope this helps

Answer:

823.98

Explanation:

Since there is only one Ba per atom you simply times 1 by 6 to get the number of mols of Ba per atom, then you times this by the atomic mass of Ba on the periodic table

Carbon Dioxide

A positive test will result in the lime water turning milky. Lime water turns milky as the Calcium hydroxide (chemical name for limewater) reacts with carbon dioxide to form Calcium Carbonate which is insoluble in water and thus forms a milky white precipitate.

The Fe is our limiting reactant here. First, convert the mass of Fe given to moles of Fe by dividing mass by the molar mass:

(51.3 g Fe)/(55.845 g/mol) = 0.9186 mol Fe.

According to the balanced equation, 2 moles of Fe2O3 are produced for every 4 moles of Fe that are consumed. In other words, half as many moles of Fe2O3 will be produced as there are Fe that react:

(0.9186 mol Fe)(2 mol Fe2O3/4 mol Fe) = 0.4593 mol Fe2O3.

Finally, convert the moles of Fe2O3 back to grams by multiplying by the molar mass of Fe2O3:

(0.4593 mol Fe2O3)(159.6882 g/mol) = 73.3 g Fe2O3.

So, 73.3 grams of Fe2O3 are formed.

Answer:

218.98 grams

Explanation:

Given that,

No. of moles, n = 2.3

The molar mass of magnesium chloride is 95.211 g/mol.

We need to find the mass of 2.3 moles of magnesium chloride.

We know that,

No. of moles = given mass/molar mass

Let m be the given mass. So,

[tex]m=n\times M\\\\=2.3\times 95.211 \\\\=218.98\ g[/tex]

So, the required mass is equal to 218.98 grams.

Answer:

15moles

Explanation:

The balanced equation of this reaction is as follows:

N2 + 3H2 → 2NH3

Molar mass of H2 = 2g/mol

mole = mass/molar mass

mole = 90/2

mole = 45moles.

Based on the above balanced equation, 1 mole of nitrogen gas (N2) reacts with 3 moles of hydrogen gas (H2)

Hence, 45moles of hydrogen gas will produce (45 × ⅓) = 15moles of nitrogen gas (N2).

Answer:

Its 14.9 for those who are doing the escape room :)

Explanation:

Answer:

The temperature at 760mmHg if the volume is still 4.2 L is 400.862 K

Explanation:

Gay Lussac's law indicates that when there is a constant volume, as the temperature increases, the pressure of the gas increases. And when the temperature is decreased, the pressure of the gas decreases. This law can be expressed mathematically as follows:

[tex]\frac{P}{T} =k[/tex]

Having an initial state 1 and a final state 2, the following is true:

[tex]\frac{P1}{T1} =\frac{P2}{T2}[/tex]

In this case:

Replacing:

[tex]\frac{560 mmHg}{295.372 K} =\frac{760 mmHg}{T2}[/tex]

Solving:

[tex]T2= 760 mmHg*\frac{295.372 K}{560 mmHg}[/tex]

T2= 400.862 K

Answer: Exothermic because the ΔH is negative.

Explanation:

The standard enthalpy of formation or standard heat of formation of a compound is the change of enthalpy during the formation of 1 mole of the substance from its constituent elements, with all substances in their standard states.

[tex]C(s)+O_2(g)\rightarrow CO_2(g)[/tex]

Exothermic reactions are those reactions in which heat is released and [tex]\Delta H[/tex] is negative.Endothermic reactions are those reactions in which heat is absorbed and [tex]\Delta H[/tex] is positive.

The reaction is exothermic as the heat is released during the formation of [tex]CO_2[/tex] as heat of formation of [tex]CO_2[/tex] is negative.

Answer:

Disturbance

Explanation:

I believe it is Disturbance because waves are normally caused by wind, and wind classifies as Disturbance.

Answer:

204.5505 grams

2.5666 moles

Explanation:

For the first question, multiply 3.5 (# of moles) by 58.443 (g/mol for NaCl).

58.443 * 3.5

I'll distribute 3.5 into 58.443.

(3.5 * 50) + (3.5 * 8) + (3.5 * 0.4) + (3.5 * 0.04) + (3.5 * 0.003)

175 + 28 + 1.4 + 0.14 + 0.0105

203 + 1.4 + 0.14 + 0.0105

204.4 + 0.14 + 0.0105

204.54 + 0.0105

204.5505 grams

There are 204.5505 grams in 3.5 moles of NaCl.

For the second question, divide 150 (# of grams) by 58.443 (g/mol for NaCl). I'll convert both into fractions.

150/1 * 1000/58443

150000/58443

2.56660336 moles

2.5666 moles (rounded to 4 places to keep consistency with the first answer) are in 150 grams of NaCl.

Because deserts have such little water vapor in the air, it makes it harder to trap heat or cold in a desert. And at night, the sun no longer heats the desert and the heat from the day doesn't stay trapped. Because of this, some deserts can get extremely cold at night, dropping to temperatures below 40F.

Hope this helps!! Have a wonderful day!!

It is actually sand, which turns the entire phenomenon hot. Sand cannot hold the heat. It acts like a mirror to the sun. During the daytime, it stays warm, and when the Sun is absent it loses all its heat making the nights colder. There’s nothing in the desert that can either absorb heat from the sun or hold it on the surface when the sun is set.

Answer:

Mountain ranges and prevailing winds.

Explanation:

Mountain ranges and prevailing winds are the factors that is responsible for the difference in the precipitation between Nevada and Washington states. The Washington state is located along the coastal region of pacific ocean and having more mountain ranges which causes more rainfall in that region while on the other hand, Nevada state comprise of plateau, basins and far away from the ocean which is the main cause of lower rainfall as compared to Washington state.

Answer:

The hydrogens of the water molecules around the bromide ion will need to be faced toward it, whereas the oxygens of the water molecules around the potassium ion will need to be faced toward it.

The strength of the interaction within the compound will supersede that of the interaction between the compound and water.

Explanation:

To answer this question, you need to be aware of the structure of a water molecule and its components. A water molecule has the chemical formula of H2O, and oxygen is inherently electronegative, meaning that it attracts electrons very strongly. As a result, when it is in H2O, it pulls the valence electrons of the H atoms very strongly, which results  in the H atoms being partially positively charged and the O atom being partially negatively charged. Therefore, the O atom is going to be attracted to the potassium ion, whereas the H atom is going to be attracted to the bromide ion.

The answer to the second part of the question is as written above because ionic bonds are stronger than ion-dipole bonds; that's just the way it is.  

Answer:

You need a balanced equation.

2Fe(s) + 3S(s) ==> Fe2S3(s) ... balanced equation

Reactants are solid iron and solid sulfur

Product is iron(III) sulfide

A. 1.42 moles Fe x 3 moles S/2 moles Fe = 2.13 moles sulfur

B. 2.75 moles S x 2 moles Fe/3 moles S = 1.83 moles iron

Answer:

[tex]186.01\ \text{mL}[/tex]

Explanation:

[tex]P_1[/tex] = Initial pressure = 1.47 atm

[tex]P_2[/tex] = Final pressure = [tex]10^5\ \text{Pa}[/tex]

[tex]T_1[/tex] = Initial temperature = [tex]44^{\circ}\text{C}[/tex]

[tex]T_2[/tex] = Final temperature = [tex]273.15\ \text{K}[/tex]

[tex]V_1[/tex] = Initial volume = 145 mL

[tex]V_2[/tex] = Final volume

We have the relation

[tex]\dfrac{P_1V_1}{T_1}=\dfrac{P_2V_2}{T_2}\\\Rightarrow V_2=\dfrac{P_1V_1T_2}{T_1P_2}\\\Rightarrow V_2=\dfrac{1.47\times 101325\times 145\times 273.15}{(44+273.15)\times 10^5}\\\Rightarrow V_2=186.01\ \text{mL}[/tex]

Final volume of the sample is [tex]186.01\ \text{mL}[/tex].

Answer: true

Explanation:

true

Answer:

Freezing point of water will decrease to -18.02°C

Explanation:

We start from the formula for freezing point depression, one of the colligative properties.

ΔT = Kf . m . i

ΔT = Freezing T° of pure solvent - Freezing T° of solution

m = molality

Kf = Cyoscopic constant (specific for each solvent)

i = numbers of ions dissolved (Van't Hoff factor)

CaCl₂ →  Ca²⁺  + 2Cl⁻    i = 3

We replace each data:

0°C - T° F) = 1.86°C/m . 3.23 m . 3

T°F = - 18.02°C

can you explain it further

Answer:

evaporation and condesation

Explanation:

because he was curiuos

Answer:

5

Explanation:

Answer: Diploid Cells (?)

Explanation:

Answer:

Endothermic and Exothermic Reactions

Endothermic and Exothermic ReactionsIn this experiment you are investigating whether dissolving ammonium nitrate in water is an endothermic or exothermic reaction. An endothermic reaction absorbs energy from its surroundings (heat), so the reaction gets colder.

Explanation:

Don't forget to mark me as brainliest answer ☺

B.

because a solute with a smaller surface area will dissolve faster

Answer:

The molar mass of the gas is 90.4g/mol

Explanation:

To solve this question we have to use the equation:

d = PM / RT

Where d is density of the gas = 2.29g/L

P is pressure = 0.75atm

M is molar mass of the gas = ??

R is gas constant = 0.082atmL/molK

T is absolute temperature = 88°C + 273.15 = 361.15K

Solving for M:

dRT / P = M

2.29L*0.082atmL/molK*361.15K / 0.75atm = M

90.4g/mol = M

The molar mass of the gas is 90.4g/mol

Answer:

(B) Grasses to Grasshoppers to Birds to Foxes

Explanation

Answer:

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