Which expression represents the concentration of OH– in solution?
a. 10–14 / [H3O+]
b. [OH–] / 10–14
c. 10–14 – [H3O+]
d. 10–14 x [H3O+]

Answer:

alpha particle needs to be added to the equation.

Explanation:

Given;

atomic mass of Americium = 241

atomic mass of neptunium = 237

The difference in atomic mass of the radioactive elements given is calculated as;

241 - 237 = 4

The particle with atomic mass of 4 is alpha particle usually represented with helium atom.

Am²⁴¹ -----> He⁴ + Np²³⁷

Thus, alpha particle needs to be added to the equation.

Answer:

4/2 HE

Explanation:

a p e x!

solid carbon dioxide, iodine, arsenic, and naphthalene

Explanation:

Examples of substances that undergo sublimation

Examples of solids that sublime are dry ice (solid carbon dioxide), iodine, arsenic, and naphthalene (the stuff mothballs are made of).

Answer:

The limiting reactant is: H₂O

265.3 g of K₂Sn(OH)₆ are formed in the reaction.

Explanation:

The reaction is:

Sn(s) + 2KOH (aq) + 4H₂O(l)  → K₂Sn(OH)₆ (s) + 2H₂ (g)

The first step to solve is to determine the moles of each reactant:

We controlled that reaction is ballanced.

122 g . 1mol / 118.71g = 1.03 moles of Sn

134g . 1mol /56.1g = 2.39 moles of KOH

63.9 g .1mol /18g = 3.55 mol of water

Stoichiometry is 1:2:4.

Sn is the lowest reactant and water, the highest, but I can see, that water is the limiting.

1 mol of Sn needs 4 moles of H₂O to react

Then, 1.03 moles of Sn may react to (1.03 . 4)/1 = 4.12 moles.

We only have 3.55 moles. It's ok.

2 moles of KOH need 4 moles of H₂O to react

Then, 2.39 moles of KOH may react to (2.39 . 4) /2 = 4.78 moles.

We only have 3.55, there's no enough water.

So 4 moles of water can produce 1 mol of potassium hydroxystannate

Then, 3.55 moles of H₂O may produce (3.55 . 1)/4 = 0.8875 moles.

We convert moles to mass: 0.08875 mol . 298.91g /1mol =265.3g

The correct answer is solution B!

Answer:

894 deg K

Explanation:

The computation is shown below:

Given that

V1 denotes the initial volume of gas = 2.00 L  

T1 denotes the initial temperature of gas = 25 + 273 = 298 K  

V2 denotes the final volume of gas  = 6.00 L  

T2 = ?

Based on the above information

Here we assume that the pressure is remain constant,

So,  

V1 ÷ T1 = V2 ÷ T2  

T2 = T1 × V2 ÷ V1

= (298)(6) ÷ (2)

= 894 deg K

Answer:

Permafrost is any part of the ground that remains completely frozen or colder

Answer:

There are 2.85 x 10^22 atoms of carbon in a diamond with a mass of 0.568 g.

Hope this helps! :)

Answer:

C. 1000

l think this is correct answer

l hope it's helpful for you

Answer:

Attached picture.

Explanation:

(1) Ksp equals the product of [Co 2+][CO3 2-]. CoCO3 is excluded from the equilibrium expression because it is a pure solid. The mole ratio of Co 2+ and CO3 2- is 1:1 so their molar solubilities are the same.

(2) There is an initial concentration of 0.10 M Co 2+ so write that in the "I" row for Co 2+ on the ICE table. When you find the zeros of the quadratic when solving for "s", take the positive value rather than the negative value because concentration cannot be negative.

(3) Extra products will cause the equilibrium to consume products and form reactants. So the reverse reaction will occur faster than the forward reaction. More products mean an increased Q value compared to K, since the numerator of [tex]K = \frac{[products]}{[reactants]}[/tex] increases.

Answer:

36 atoms

Explanation:

The reactants are in the left side of the equation. First we determine how many atoms are there in the C₆H₁₂O₆ molecule:

There are two atoms in a O₂ molecule, and there are 6 O₂ molecules in the equation:

The total number of atoms in the reactants is

Answer:

There are 36 grams in 4.00 moles of Carbon.

Explanation:

In order to convert from moles of a substance into grams of the same substance, we need to use the substance's molar mass.

That means that in this case we use the molar mass of Carbon:

Thus, there are 36 grams in 4.00 moles of Carbon.

Answer:

9 moles

Explanation:

The balanced chemical equation provided in this question is as follows:

2CH₄ + S₈ → 2CS₂ + 4H₂S

In accordance to the above balanced equation, 1 mole of sulphur (S8) produces 4 moles of hydrogen sulfide (H2S).

Therefore, if 2.25mol of S8 is used, 2.25 × 4 = 9 mol

9 moles of H2S is produced.

Answer:

Fires --> These consume fuel and convert chemical energy stored in that fuel into thermal light and sound energy.

Decay -->The breakdown of dead plants and animals releases thermal energy.

Earth --> Thermal energy comes from deep inside and it is called geothermal energy.

Answer:

Calcium flouride?

Explanation:

Quite self explanatory

Answer:

The number of protons in one atom of an element determines the atom's identity, and the number of electrons determines its electrical charge. The atomic number tells you the number of protons in one atom of an element. It also tells you the number of electrons in a neutral atom of that element.

Explanation:

Answer:

A.

Explanation:

In an endothermic reaction heat is applied.

In an endothermic process, heat is transferred from the surroundings to the system.

What are endothermic and exothermic processes?

An exothermic process is one that gives off heat. This heat is transferred to the surroundings. An endothermic process is one in which heat has to be supplied to the system from the surroundings.

The endothermic process is a term that describes a reaction where the system absorbs the energy from its surrounding in the form of heat. A few examples of the endothermic process are photosynthesis, evaporating liquids, melting ice, etc.

The exothermic reaction is the opposite of an endothermic reaction. It releases energy by light or heat to its surrounding. A few examples are neutralization, burning of a substance, reactions of fuels, etc.

Hence, option A is the correct answer.

Learn more about endothermic and exothermic processes here:

https://brainly.com/question/4345448

#SPJ2

Answer:

B.) 14

Explanation:

27-13=14 neutrons

Answer:

about 5 hours

Explanation:

When doing this problem you mmust mulitiply 4 x 74 and divide the answer by 60 because 60=1 hour.

Answer:

HCO₂

Explanation:

From the information given:

The mass of the elements are:

Carbon C = 26.7 g;     Hydrogen H = 2.24 g     Oxygen O = 71.1 g

To determine the empirical formula;

First thing is to find the numbers of moles of each atom.

For Carbon:

[tex]=26.7 \ g\times \dfrac{1 \ mol }{12.01 \ g} \\ \\ =2.22 \ mol \ of \ Carbon[/tex]

For Hydrogen:

[tex]=2.24 \ g\times \dfrac{1 \ mol }{1.008 \ g} \\ \\ =2.22 \ mol \ of \ Hydrogen[/tex]

For Oxygen:

[tex]=71.1 \ g\times \dfrac{1 \ mol }{1.008 \ g} \\ \\ =4.44 \ mol \ of \ oxygen[/tex]

Now; we use the smallest no of moles to divide the respective moles from above.

For carbon:

[tex]\dfrac{2.22 \ mol \ of \ carbon}{2.22} =1 \ mol \ of \ carbon[/tex]

For Hydrogen:

[tex]\dfrac{2.22 \ mol \ of \ carbon}{2.22} =1 \ mol \ of \ hydrogen[/tex]

For Oxygen:

[tex]\dfrac{4.44 \ mol \ of \ Oxygen}{2.22} =2 \ mol \ of \ oxygen[/tex]

Thus, the empirical formula is HCO₂

Answer:

0.015M is the final molarity of the NaOH solution

Explanation:

A solution of 0.040M NaOH is diluted from 150mL to 250mL + 150mL = 400mL. That means the solution is diluted:

400mL / 150mL = 2.667 times.

As the original solution has a concentration of 0.040M, the diluted solution has a concentration of:

0.040M / 2.667 =

Answer:

slightly but poorly

Explanation:

it is a white crystalline solid that is practically insoluble in water and soluble in ether, chloroform, carbon disulfide, benzene, alcohol and acetone.

Answer: 1. Highest osmotic pressure : 1 M [tex]MgCl_2[/tex]

2. Lowest osmotic pressure:  1 M [tex]C_{12}H_{22}O_{11}[/tex]

Explanation:

[tex]\pi=i\times C\times R\times T[/tex]

[tex]\pi[/tex]= osmotic pressure

i = Van'T Hoff factor  

C = concentration  

T = Temperature  

1. For 1M [tex]MgCl_2[/tex]  

, i= 3 as it is a electrolyte and dissociate to give 3 ions.

[tex]MgCl_2\rightarrow Mg^{2+}+2Cl^{-}[/tex]  

2. For 1 M [tex]KCl[/tex]

, i= 2 as it is a electrolyte and dissociate to give 2 ions.

[tex]KCl\rightarrow K^{+}+Cl^{-}[/tex]

3. For  1M [tex]C_{12}H_{22}O_{11}[/tex]

, i= 1 as it is a non electrolyte and do not dissociate.  

Thus as vant hoff factor is highest for [tex]MgCl_2[/tex] thus osmotic pressure is highest for 1 M [tex]MgCl_2[/tex]

And as vant hoff factor is lowest for [tex]C_{12}H_{22}O_{11}[/tex] thus osmotic pressure is lowest for  1 M [tex]C_{12}H_{22}O_{11}[/tex]

Answer:

14

Explanation:

Step 1: Calculate the moles corresponding to 25 g of Ba(OH)₂

The molar mass of Ba(OH)₂ is 171.34 g/mol.

25 g × 1 mol/171.34 g = 0.15 mol

Step 2: Calculate the molar concentration of Ba(OH)₂

Molarity is equal to the moles of solute divided by the liters of solution.

[Ba(OH)₂] = 0.15 mol/0.250 L = 0.60 M

Step 3: Calculate the molar concentration of OH⁻

Ba(OH)₂ is a strong base according to the following equation.

Ba(OH)₂ ⇒ Ba²⁺ + 2 OH⁻

The molar ratio of Ba(OH)₂ to OH⁻ is 1:2. The molar concentration of OH⁻ is 2/1 × 0.60 M = 1.2 M.

Step 4: Calculate the concentration of H⁺

We will use the ionic product of water expression.

Kw = 1.0 × 10⁻¹⁴ = [H⁺] × [OH⁻]

[H⁺] = 1.0 × 10⁻¹⁴/[OH⁻] = 1.0 × 10⁻¹⁴/1.2 = 8.3 × 10⁻¹⁵ M

Step 5: Calculate the pH of the solution

We will use the definition of pH.

pH = -log [H⁺] = -log 8.3 × 10⁻¹⁵ = 14

Answer:

2.41x10²¹ atoms

Explanation:

mass of nickel that are present in the coin can be determined Using ( 25% nickel) with j mass of coin= 0.942g )

mass of nickel = (0.942g) × (25/100)

= 0.2355g of Nickel

We need to convert this " gram" into " moles"

Mole= mass/ molar mass

Molar mass= 58.69 g/mol

0.2355 g) / (58.69 g/mol)

= 0.004 mol

We need to convert the moles to

number of atoms.

Avogadro's number= 6.023x10²³ atoms/mol

(0.004 × 6.023x10²³ atoms/mol)

=2.41x10²¹ atoms

Answer:

[tex]\boxed {\boxed {\sf \frac {1}{3} \ mol \ Al_2O_3 \approx 0.34 \ mol \ Al_2O_3}}[/tex]

Explanation:

We will use stoichiometry to solve this problem. The reaction given has a formula of

[tex]4Al+3O_2 \rightarrow 2Al_2O_3[/tex]

The coefficients tell us the number of moles necessary for the reaction.

The reaction requires 3 moles of oxygen to produce 2 moles of aluminum oxide. We can make a ratio.

[tex]\frac {3 \ mol \ O_2}{ 2\ mol \ Al_2O_3}}[/tex]

Since we are doing the reaction with 0.5 moles of oxygen, we multiply the ratio by that number.

[tex]0.5 \ mol \ O_2 *\frac {3 \ mol \ O_2}{ 2 \ mol \ Al_2O_3}}[/tex]

Flip the ratio so the moles of oxygen cancel each other out.

[tex]0.5 \ mol \ O_2 *\frac {2 \ mol \ Al_2O_3}{ 3 \ mol \ O_2}}[/tex]

[tex]0.5 *\frac {2 \ mol \ Al_2O_3}{ 3 }[/tex]

[tex]\frac {1 \ mol \ Al_2O_3}{ 3 }[/tex]

[tex]\frac {1}{3} \ mol \ Al_2O_3 = 0.33333 \ mol \ Al_2O_3 \approx 0.34 \ mol \ Al_2O_3[/tex]

0.5 moles of oxygen produces 1/3 or approximately 0.34 moles of aluminum oxide.

Answer:

4.5M

Explanation:

The solution was diluted from 2.0L to 3.0L, the dilution factor was:

3.0L / 2.0L = 1.5.

That means the solution was diluted 1.5 times.

As the final molarity of the diluted solution is 3.0M, the initial molarity of the solution was:

3.0M * 1.5 =