When hydrogen reacts with calcium metal, what are the oxidation numbers of the calcium and hydrogen in the CaH2 product?

Ca(s)+ H2(g) → CaH2

a. +2 and -1
b. +1 and -2
c. +2 and 2
d. 0 and 0
e. -2 and +1

Answer:

Molality = 8.57 m

Explanation:

Given data:

Molarity of solution = 5.73 M

density = 0.9327 g/mL

Molality of solution = ?

Solution:

Molality = moles of solute / kg of solvent.

Kg of solvent:

Mass of 1 L solution = density× volume

Mass of 1 L solution = 0.9327 g/mL × 1000 mL

Mass of 1 L solution = 932.7 g

Mass of solute:

Mass of 1 L = number of moles  × molar mass

Mass = 5.73 mol  × 46.068 g/mol

Mass = 263.97 g

Mass of solvent:

Mass of solvent = mass of solution - mass of solute

Mass of solvent = 932.7 g - 263.97 g

Mass of solvent = 668.73 g

In Kg = 668.73 /1000 = 0.6687 Kg

Molality:

Molality = number of moles of solute / mass of solvent in Kg

Molality = 5.73 mol /  0.6687 Kg

Molality = 8.57 m

Considering the definition of molality , you obtain that the molality of a 5.73 M ethanol (C₂H₅OH) solution whose density is 0.9327 g/mL is 8.57 [tex]\frac{moles}{kg}[/tex].

Molality is the ratio of the number of moles of any dissolved solute to kilograms of solvent.

The Molality of a solution is determined by the expression:

[tex]Molality=\frac{number of moles of solute}{kilogramof solvent}[/tex]

You have a 5.73 M ethanol (C₂H₅OH) solution whose density is 0.9327 g/mL.

Molarity is the number of moles of solute that are dissolved in a certain volume.

In this case, taking into account that the volume considered is 1 L, the number of moles of solute is 5.73 moles.

On the other side, density is the ratio of the weight (mass) of a substance to the volume it occupies. So, being 1 mL= 0.001 L, 0.9327 g/mL means that you have 0.9327 grams per 1 mL or 932.7 g per 1 L.

So, being the mass of solution calculated as number of moles multiplied by the molar mass, and being the mass of the solution 932.7 grams in 1 L, the mass of water is:

Mass of solvent = mass of solution - mass of solute

Mass of solvent = mass of solution - number of moles× molar mass

Mass of solvent = 932.7 g - 5.73 mol× 46.068 g/mol

Mass of solvent = 932.7 g - 263.97 g

Mass of solvent = 668.73 g= 0.66873 kg

Then, the molality can be calculated as:

[tex]Molality=\frac{5.73 moles}{0.66873 kg}[/tex]

Solving:

molality= 8.57 [tex]\frac{moles}{kg}[/tex]

Finally, the molality of a 5.73 M ethanol (C₂H₅OH) solution whose density is 0.9327 g/mL is 8.57 [tex]\frac{moles}{kg}[/tex].

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Number of doses needed : 4 doses

Given

weight of the child : 25 kg

Treatment of Benadryl : 5 mg/kg weight

The concentration of Benadryl : 12.5 mg/5 ml

1 dose = 12.5 ml

Required

Number of doses needed

Solution

Amount of Benadryl for 25 kg weight :

[tex]\tt 25~kg\times 5~\dfrac{mg}{kg}=125~mg[/tex]

Amount of Benadryl solution :

[tex]\tt \dfrac{125~mg}{12.5~mg/5~ml}=125~mg\times \dfrac{5~ml}{12.5~mg}=50~ml[/tex]

Amount of doses :

[tex]\tt \dfrac{50~ml}{12.5~ml}=4~doses[/tex]

Answer:

C.

Explanation:

Answer:

the answer is the second choice actual force

Answer:

the answer is a true

Explanation:

Thiols, sulfides and disulfides have high solubility in water. This statement is true. Therefore, option A is correct.

Solubility refers to a substance's ability to form a solution with another substance, the solvent. The inability of the solute to form such a solution is referred to as insolubility.

Temperature, pressure, polarity, and molecular size are all factors that influence solubility. For most solids dissolved in liquid water, solubility increases with temperature. This is due to increased vibration or kinetic energy of the solute molecules at higher temperatures.

A rise in temperature stresses the equilibrium condition, causing it to shift to the right. Because the dissolving process consumes some of the heat, the stress is reduced. As a result, as the temperature rises, so does the solubility.

Thus, option A is correct.

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Answer:

0.095 moles of O₂ are left over.

Explanation:

First of all, state the balanced reaction:

2NO + O₂ → 2NO₂

We determine moles of each reactant:

20.2 g . 1mol / 30g =  0.673 moles of NO

13.8g . 1mol / 32g = 0.431 moles of oxygen

Oxygen is the excess reactant. Let's see.

For 2 moles of NO I need 1 mol of O₂

Then, for 0.673 moles of NO I may use (0.673 .1) /2 = 0.336 moles

I have 0.431 moles of O₂ and I only need 0.336 mol. According to reaction, stoichiometry is 2:1.

In conclussion, the moles of excess reactant that will be left over:

0.431 - 0.336 = 0.095 moles

[tex]\boxed{\boxed{\pink{\bf \leadsto This \ is \ an \ example \ of \ Chemical \ change .}}}[/tex]

Reaction of sodium metal with water is a chemical change . Sodium reacts with water to form sodium hydroxide. This is also an example of exothermic reaction as heat is released in this process. Sodium reacts vigoursly with water , it even reacts with the moisture present in the air . So it is stored in kerosene oil .

The reaction of sodium with water is :-

[tex]\boxed{\red{ \bf \underset{\blue{Sodium}}{2Na} + \underset{\blue{Water}}{2H_2O} \longrightarrow \underset{\blue{Sodium\: Hydroxide}}{2Na(OH)}+ \underset{\blue{Hydrogen}}{H_2}}}[/tex].

The reaction of sodium metal with water is a chemical change, as a result formation of sodium hydroxide occurs.

The following points to be noted for the reaction of sodium with water:

Therefore, the reaction of sodium with water is a chemical change.

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Answer:

125.59528999999982

Explanation:

Answer:

CnH2n-2

im pretty sure thats the answer

Moles of Ca (OH)₂ required to completely neutralize 3.26 mol of HC₂H₃O₂ : 1.63

A reaction coefficient is a number in the chemical formula of a substance involved in the reaction equation. The reaction coefficient is useful for equalizing reagents and products.

Reaction

2HC₂H₃O₂ + Ca(OH)₂ → Ca(C₂H₃O₂)₂ + 2H₂O

mol of HC₂H₃O₂ = 3.6

From equation above, mol ratio of HC₂H₃O₂ : Ca(OH)₂ = 2 : 1, so mol Ca(OH)₂ :

[tex]\tt mol~Ca(OH)_2=\dfrac{1}{2}\times 3.26=1.63[/tex]

Answer:

Physical Property

Explanation:

As there is no chemical change or chemical related stuff in it!

Answer:

physical

Explanation:

Answer:

There are [tex]12[/tex] electrons with [tex]l = 1[/tex] in each [tex]\rm _{21}Sc[/tex] atom in its ground state.

Explanation:

The azimuthal quantum number (with symbol [tex]l[/tex]) of an electron in an atom specifies the type of the orbital that contains this electron.

For example:

The question is asking for the number of electrons with [tex]l = 1[/tex] in each [tex]\rm _{21}Sc[/tex] atom. Because [tex]l = 1\![/tex] corresponds to [tex]p[/tex] orbitals, this question is equivalently asking for the number of electrons in [tex]p\![/tex] orbitals in one such atom.

Find the electron configuration of a ground-state [tex]\rm _{21}Sc[/tex] atom:

[tex]1s^{2}\; 2s^{2}\; 2p^{6}\; 3\, s^{2}\; 3\, p^{6}\; 3d^{1}\; 4s^{2}[/tex].

In other words, there are [tex]12[/tex] electrons in [tex]p[/tex] orbitals in total in a ground-state [tex]\rm _{21}Sc[/tex] atom in total; [tex]l = 1[/tex] for each of these electrons because of the

Therefore, a ground-state [tex]\rm _{21}Sc[/tex] atom would include [tex]12[/tex] electrons with [tex]l = 1[/tex].

Answer:

You are not at sea level.

Explanation:

Assuming empirical observation shows boiling point 'below' 100°C then one concludes boiling experiment is being conducted above sea level where air pressure is lower than sea level air pressure. Generally, it is accepted in most literature publications that atmospheric pressure decreases ~1-inch per 1000-ft increase in elevation.

By definition, the boiling point of a liquid occurs when the atmospheric pressure equals fluid vapor pressure. Thus, if experimentally a water sample  boils less than 100°C then one can only conclude the atmospheric pressure is lower than that needed to boil water at sea level atmospheric pressure; i.e., observed boiling point is at elevation greater than sea level.

One can calculate the boiling point of a liquid relative to sea level boiling point by using the Clausis-Clapeyron Equation.

ln(VP₂/VP₁) = ΔH(vap)/R(T₁ - T₂/T₁·T₂) solve for T₂ given Heat of Vaporization of water (ΔH(vap) = 28.2 Kj/mol) at specified temperature (T₁ at sea level = 273 Kelvin - standard) and R = 0.008314 Kj/mol-K).

A single bond contains two shared electrons.

Answer:

H20

Explanation:

Answer:

The answer is H20

Explanation:

Answer:

False

Explanation:

I got 100 on the test on edge

Answer:

an emotional appeal to emphasize the United States' commitment to justice

Explanation:

The main type of appeal that Kennedy uses in this excerpt is an emotional appeal to emphasize the United States' commitment to justice. Therefore, option B is correct.

In rhetoric, an appeal is a persuasive approach used to persuade an audience to believe or do something. Appeals can take many forms, but they generally fall into three categories: pathos, ethos, and logos.

Pathos appeals to the audience's emotions, ethos appeals to the credibility of the speaker or source, and logos appeals to the audience's sense of logic and reason.

Effective communication usually involves the use of multiple appeals to convince the audience to accept a particular perspective or take a particular action. Therefore, option B is correct.

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Answer:

This question appear incomplete

Explanation:

This question appear incomplete because of the absence of options. However, it seeks to differentiate between a scalar and a vector quantity. A scalar quantity is a quantity with just magnitude but no direction (example is mass) while a vector quantity is a quantity with both magnitude and direction. Thus, a quantity needs direction to complete it's description when such quantities is a vector quantity such as weight (which is the downward force/gravity acting on an object with relative mass). The mass is the magnitude while the gravity/downward force is the direction. It would just be a scalar quantity if it had just mass and no downward force (as in direction) acting on it.

Answer:

0.342 m

Explanation:

From the question given above, the following data were obtained:

Mass of NaBr = 14.57 g

Mass of water = 415 g

Molar mass of NaBr = 102.89 g/mol

Molality of NaBr =?

Next, we shall determine the number of mole in 14.57 g of NaBr. This can be obtained as follow:

Mass of NaBr = 14.57 g

Molar mass of NaBr = 102.89 g/mol

Mole of NaBr =?

Mole = mass / molar mass

Mole of NaBr = 14.57 / 102.89

Mole of NaBr = 0.142 mole

Next, we shall convert 415 g of water to kg. This can be obtained as follow:

1000 g = 1 Kg

Therefore,

415 g = 415 g × 1 Kg / 1000 g

415 g = 0.415 Kg

Thus, 415 g is equivalent to 0.415 Kg.

Finally, we shall determine Molality of the solution as follow:

Mole of NaBr = 0.142 mole

Mass of water = 0.415 Kg

Molality of NaBr =?

Molality = mole / mass of water in Kg

Molality of NaBr = 0.142 / 0.415

Molality of NaBr = 0.342 m

Therefore, the molality of NaBr solution is 0.342 m.

Answer:

0.341

Explanation:

as stated underneathe the 'tutor verified' answer. lol

Answer:

A highly positive ion was attracted to a membrane and their locations is explained in details.

Explanation:

1.

The Head of a lipid is hydrophilic (polar). This cover can be bearing negative or positive charges. This is that charge that creates the head hydrophilic(communicate with water(a polar molecule, including negative and positive unfair charges).

The tail is hydrophobic (non-polar). This part doesn't include any charge that enhances hydrophobic. (Does not combine with water.

Now a positive ion can be brought only to electron-rich stations. We cannot say that this situation is forever the hydrophilic part.

A dual bond is an electron-rich situation. So the ion will be drawn to the dual bond place of a lipid.

2.

A conveyor that needs energy is active transport.

3.

The use of a membrane is to stop the particles and ions from passing crosswise it openly. So through the membrane, in an active carrier, we require input energy to transfer molecules beyond it.

Answer:

2 is the answer your welcom

Answer:

B. 138

Explanation:

Based on isotope notation:

[tex]^X_nA[/tex]

For the atom A, the mass number, X, is the sum of neutrons and protons and

n is the number of protons = Atomic number.

The number of protons depends of the nature of the atom. For example, Carbon has 12 protons, hydrogen 1 and Radium has 88 protons.

The radium-226 means the mass number is 226. Thus, number of neutrons are:

Mass number - Atomic number

226 - 88 = 138

Right answer is:

Answer:

Unit 4 Lesson 2:

Energy Release Quick Check

1. 138 neutrons

2. The conversion of an atom of one element into a different element through nuclear changes.

3. A nuclear equation is balanced according to mass number. A chemical equation is balanced according to the total mass before and after the change.

4. 82

5. Some of the matter is converted to energy.

Please give me Brainliest. You're Welcome

Answer:

titanium

Explanation:

The ion has a charge of +2 since each of the chrlorine atoms have a charge of -1. if x has 20 electrons, the it must have 22 protons to get a charge of +2. The proton number defines the element, so the element with 22 protons is titanium.

Answer:

Lymphocytes

Explanation:

Pathogens are particles that make you sick like bacteria, viruses, amoebas. Water is essential for life but that's for metabolism, not fighting off against infection or viruses.

Answer:

Lymphocytes

Explanation:

lymphocytes are a kind of white blood cell (WBC). Lymphocytes are cells of the immune system and help fight infection. Lymphocytes live in lymph nodes, but also in the bloodstream and all over the body. Lymphocytes come in two main types: B-cells and T-cells

Where as water is totally not white blood cells and pathogens are viruses and bacterium

Answer:

60 g/ mol

Explanation:

Carbon, C 12

Hydrogen, H 1

Oxygen, O 16

Molar mass = 12+3+12+16+16+1 = 60 g/ mol

Answer:

The density of something is the connection between the mass of the substance and how much space it takes up

Answer:

c2h4s

Explanation:

You can reduce s2 to s

Answer: Electricity

Explanation: Electricity is the movement of matter. not matter itself

A. 21.47 atm

B. 0.4737 mol

C. 0.900moles of O2

1.200 moles of CO2

1.200 moles of H2O

2.400 mol of Ne that doesn't react.

Ideal gas law is valid only for ideal gas not for vanderwaal gas. Therefore,  the total pressure in the cylinder is 21.4atm. Ideal gas is a hypothetical gas.

Ideal gas equation is the mathematical expression that relates pressure volume and temperature. Vanderwaal gas behave as ideal gas at low pressure and high temperature.

Mathematically,

PV=nRT

where,

P = pressure=?

V= volume=7.80 L

n =number of moles=2.700 mol +0.600 mol +2.400 mol

                                =5.7moles

T =temperature = 358 K

R = Gas constant = 0.0821 L.atm/K.mol

substituting all the given values in the above equation, we get

P × 7.80 L =5.7moles× 0.0821 L.atm/K.mol × 358 K

On calculations, we get

P =21.4atm

Therefore,  the total pressure in the cylinder is 21.4atm.

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