Examples 36

   

A cylinder is 350cm³ long and two gases A and B have relative molecular weights of 64 and 16 respectively. If the two gases, at the same temperature and pressure, are released simultaneously at both ends determine the distance from one end at which the gases meet.​

Answer:

33

Explanation:

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:

-74.6 kj/mol

Explanation:

you can see the answer at the pic

parts per million (ppm), parts per billion (ppb) and parts per trillion (ppt) are the most commonly used terms to describe very small amounts of substances. a ppm of a chemical in water means that, in a million units of water, there would only be one unit of the chemical.

Answer:

Carbon-12

Explanation:

Carbon-12 is a carbon with 6 protons and 6 neutrons. Since the AMU for an element is calculated by averaging all naturally occurring isotopes, we can see that 12 in the most abundant. (Since 12.01 is very close to 12, the only reason it is not exactly 12 is because there are other isotopes like carbon-13 or carbon-14 but in low amounts)

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:

blocks 1 and 2 the rhdh huff hgfhh5

matter is anything that has mass and volume...it has three state thus solid, liquid and gas.. It possess chemical and physical changes.

Answer:

7836.6 J

Explanation:

The following data were obtained from the question:

Heat of fusion (Hf) = 0.148 KJ/g

Mass (m) = 52.95 g

Heat (Q) required =..?

The heat (Q) required to melt the sample of nephthalene can be obtained as follow:

Q = m·Hf

Q = 52.95 × 0.148

Q = 7.8366 KJ

Finally, we shall convert 7.8366 KJ to Joule (J) in order to obtain the desired result. This can be obtained as follow:

1 kJ = 1000 J

Therefore,

7.8366 KJ = 7.8366 KJ × 1000 J / 1 KJ

7.8366 KJ = 7836.6 J

Therefore, 7.8366 KJ is equivalent to 7836.6 J

Thus, 7836.6 J of heat energy is required to melt the sample of nephthalene.

The heat required for melting of 52.95 g of naphthalene has been 7.8366 kJ.

The heat of fusion has been the energy required by 1g for the change in the substance.

The heat required to melt naphthalene can be given as:

Heat = mass × Heat of fusion

The given mass = 52.95 g

The heat of fusion = 0.148 kJ/g

The heat required can be given as:

Heat = 0.148 × 52.95 kJ

Heat = 7.8366 kJ.

The heat required for melting of 52.95 g of naphthalene has been 7.8366 kJ.

For more information about the heat of fusion, refer to the link:

https://brainly.com/question/25475410

Answer:

im just trying to get work done i will help u if i knew it

Answer:

A. it is a strong basic solution

Answer:

(see below)

Explanation:

First, refer to the pH scale:

1  2  3  4  5  6        7        8  9  10  11  12  13  14

<==  acidic        neutral             basic  ==>

You can see that the smaller the number, the stronger the acid and the bigger the number, the more basic the base is. 7 is neutral, such as water. it's neither basic nor acidic.

Now, using the process of elimination:

A) It's a strong basic solution.

No, because this solution's pH hasn't even reached basic.

B) It's a weak acidic solution.

Yes, because it is acidic and it's just a little bit more acidic than a neutral solution.

C) It's a weak basic solution.

No, because this solution's pH hasn't even reached basic.

D) It's a strong acidic solution.

No, because even though it's acidic, it's just below neutral. For something to be a strong acidic solution would be around a pH of 3.

So the answer would be B) It's a weak acidic solution.

Answer:

G is correct option:

# of Ba atoms = coefficient 4 × subscript 1= 4

Explanation:

Formula:

4Ba(OH)₂

G is correct option:

# of Ba atoms = coefficient 4 × subscript 1= 4

Because there are only 4 atoms of Ba in given formula.

Ba(OH)₂ contain one atom of Ba while in question there are 4 moles of Ba(OH)₂ present thus total 4×1 = 4 atoms of Ba present.

Other options are incorrect. Because,

F:

# of Ba atoms = coefficient 4 + subscript 1 = 5

This shows given formula contain 5 Ba atoms. So it is incorrect.

H:

# of Ba atoms = subscript 4 ×  coefficient 2 = 6

This shows that subscript is 4 which is incorrect because coefficient is 4 and subscript is 1.  

j:

# of Ba atoms = subscript 1  + coefficient 1 = 2

This option shows that subscript is one which is correct but coefficient is incorrect. The coefficient of Ba is 4 and coefficient is always multiply with subscript not added. So this option is also incorrect.

Answer:

[tex]C_{3}H_4O_2[/tex]

Explanation:

Hello,

In this case, since the carbon of the initial compound is present in the carbon dioxide product, we can compute the mass and moles of carbon in the compound:

[tex]n_C=91.8g CO_2*\frac{1molCO_2}{44gCO_2} *\frac{1molC}{1molCO_2} =2.09molC\\\\m_C=91.8g CO_2*\frac{1molCO_2}{44gCO_2} *\frac{1molC}{1molCO_2}*\frac{12gC}{1molC} =25.0gC[/tex]

Next, the mass and moles of hydrogen in the compound, is contained in the yielded amount of water, thus, we compute the mass and moles of hydrogen in the compound:

[tex]n_H=25.1gH_2O*\frac{1molH_2O}{18gH_2O} *\frac{2molH}{1molH_2O} =2.79molH\\\\m_H=25.1gH_2O*\frac{1molH_2O}{18gH_2O} *\frac{2molH}{1molH_2O} *\frac{1gH}{1molH} =2.79gH[/tex]

In such a way, the mass of oxygen comes from the mass of the compound minus the mass of carbon and oxygen:

[tex]m_O=50.1g-25.0g-2.79g=22.31gO[/tex]

And the moles:

[tex]n_O=22.31gO*\frac{1molO}{16gO}=1.39molO[/tex]

Then, we compute the subscripts by diving the moles of C, H and O by the moles of oxygen as the smallest moles:

[tex]C:\frac{2.09}{1.39}=1.5 \\\\H:\frac{2.79}{1.39}=2\\ \\O:\frac{1.39}{1.39} =1[/tex]

After that, we write:

[tex]C_{1.5}H_2O[/tex]

Which must be shown in whole number only, thereby we multiply the subscripts by 2, so the empirical formula turns out:

[tex]C_{3}H_4O_2[/tex]

Best regards.

Answer:

Liquids are usually less dense than solids but more dense than air. Temperature can change a liquid's density. For example, increasing the temperature of water causes the molecules to spread farther apart. The farther apart the molecules are, the less dense the water is.

Answer:

Solids are usually much more dense than liquids and gases, but not always.

Explanation:

Mercury, a metallic element that is a liquid at room temperature, is denser than many solids. Aerogel, a very unusual human-made solid, is about 500 times less dense than wate

Answer:

Lithium (Li)

Explanation:

It has an atomic number of 3.

Answer:

D

Explanation:

Because i just added all of numbers up

C. 24 if the zero after the 6H, is supposed to be a zero however if it wasnt and u were trying to say h2o it'd be 36

Answer:

about 0.13 mol

Explanation:

To find number of mols when given grams you first have to find the molar mass of the compound. This is done by adding up the atomic masses of the element in the compound. So Sr= 88 g/mol S=32 g/mol and O=16 g/mol. Then 88+32+(16x4)=184. Then using this you can convert from grams to mols by dividing the grams by the molar mass. So, 24.23/184 equals about 0.13 mol.

Answer:

The elements with completely filled shells are classified as noble gases

That is why we only see noble gases on the rightmost corner of the periodic table, it is because they have the maximum number of electrons in a shell

Examples of noble gases

Helium , Neon , Argon and Krypton are some examples of noble gases

Answer:

Explanation:

I JUST TOOK THE TEST!

Answer : The mole ratio of [tex]PCl_3[/tex] to [tex]PCl_5[/tex] is 1 : 1.

Explanation :

Balanced chemical reaction : It is a chemical reaction in which the number of atoms of individual elements present on reactant side must be equal to the product side.

The balanced chemical reaction is:

[tex]PCl_3+Cl_2\rightarrow PCl_5[/tex]

By the stoichiometry of the reaction we can say that 1 mole of [tex]PCl_3[/tex] reacts with 1 mole of [tex]Cl_2[/tex] to give 1 mole of [tex]PCl_5[/tex].

From this we conclude that the mole ratio of [tex]PCl_3[/tex] to [tex]PCl_5[/tex] is 1 : 1.

Hence, the mole ratio of [tex]PCl_3[/tex] to [tex]PCl_5[/tex] is 1 : 1.

Answer:

A

Explanation:

Answer: 2681.81

Explanation:

Answer:

Explanation:

The volume of a substance when given the density and mass can be found by using the formula

[tex]volume = \frac{mass}{density} \\ [/tex]

From the question we have

[tex]volume = \frac{12}{2.7} \\ = 4.4444444....[/tex]

We have the final answer as

Hope this helps you

Answer:

mass = density × volume = 0.67 × 1.00 = 0.67 kg = 670 g. The molar mass of octane, C8H18, is 8 × 12.01 (C) + 18 × 1.008 (H) = 114.224.

Explanation:

Answer:

N=2

H=6

Explanation:

1.Balance a chemical equation in terms of moles.

2.Use the balanced equation to construct conversion factors in terms of moles.

3.Calculate moles of one substance from moles of another substance using a balanced chemical equation.

The law of conservation of matter says that matter cannot be created or destroyed. In chemical equations, the number of atoms of each element in the reactants must be the same as the number of atoms of each element in the products.

(P.s it could also be where you have to solve it in which you have to simplify it first then solve it.) like adding them all up.

Hope this is the answer. :)

Answer:

Explanation:

moles of potassium dichromate = .0250 x .026 = 65 x 10⁻⁵ moles

1 mole of potassium dichromate reacts with 6 moles of Fe⁺²

65 x 10⁻⁵ moles of potassium dichromate will react with

6 x 65 x 10⁻⁵ moles of Fe⁺²

= 390 x 10⁻⁵ moles

390 x 10⁻⁵ moles are contained in 25 mL of solution

molarity of solution = 390 x 10⁻⁵ / 25 x 10⁻³

= 15.6 x 10⁻² M  .

Answer:

There are 0.017252 moles in SnO2

Explanation:

n= m/M

n=2.6/(118.710 + 2(16))

n= 2.6/150.71

n= 0.017252

Remeber to round based on the significant digits in the question.

Answer:

d) this is an exothermic reaction.

Explanation:

The reaction between HCl and KOH results in an increase in temperature in the solution. Select the correct statement from the list below.

a) this is an endothermic reaction . NO. This would cause a decrease in the temperature of the solution.

b) this is a phase change reaction . NO. All the species remain in the aqueous phase.

c) this is a vaporization reaction . NO. All the species remain in the aqueous phase.

d) this is an exothermic reaction. YES. The reaction releases heat, so it is exothermic.