whats the answer giving brainliest :))))

Answer:

c

Explanation:

8.4

For the reaction H₂SO₄ + 2NaC≡N → 2HC≡N + Na₂SO₄, we have that 8.4 moles of sodium cyanide are needed to produce 4.2 moles of sodium sulfate (option C).

The reaction between sodium cyanide and sulfuric acid is:  

H₂SO₄ + 2NaC≡N → 2HC≡N + Na₂SO₄

We can find the number of moles of sodium cyanide, assuming that it is the limiting reactant and knowing that 2 moles of it produce 1 mol of sodium sulfate, as follows:  

[tex] n_{NaC\equiv N} = \frac{2\: moles\: NaC\equiv N}{1 \: mol\: Na_{2}SO_{4}}*4.2 \: moles\: Na_{2}SO_{4} = 8.4 \: moles [/tex]  

Therefore, 8.4 moles of sodium cyanide are needed to produce 4.2 moles of sodium sulfate (option C).  

Learn more about limiting reactants here:

brainly.com/question/14225536

I hope it helps you!                

Answer:

Explanation:

To find the number of moles in a substance given it's number of entities we use the formula

[tex]n = \frac{N}{L} \\[/tex]

where n is the number of moles

N is the number of entities

L is the Avogadro's constant which is

6.02 × 10²³ entities

From the question we have

[tex]n = \frac{1.68 \times {10}^{24} }{6.02 \times {10}^{23} } \\ = 2.790697 ...[/tex]

We have the final answer as

Hope this helps you

Answer:

highly unstable

Explanation:

also, due to repulsion of lone pairs and instability it breaks and can't form PI5

hope that helps....

Explanation:

The highest number is the strongest base. Therefore the pH of 12 is the strongest base here (C).

Answer:

B: Pineapple imported by air from Costa Rica

Explanation:

Embodied energy is the total energy that is required for the extraction, processing, manufacture and transportation of materials to its intended usage destination.

This means highest embodied energy will be the work that demands the most energy for extraction, processing, manufacture and transportation of materials to its intended usage destination.

Looking at the options given, the one with the highest embodied energy will be "Pineapple imported by air from Costa Rica". This is because other options are done locally and thus will consume lesser energy and processing time unlike the pineapple that is coming from another country and by air.

Answer:

Metre

Explanation:

the SI unit of length is Metre

Answer:

The SI unit for length is Meter

Answer:

EASY ITS BUILT DIFERENT

Explanation:

Answer:

I⁻

Explanation:

The identity of the element is obtained when the proton number is known.

Mass Number = 127

Neutrons = 74

Number of protons is obtained from;

Protons = Mass Number - Number of Neutrons

Protons = 127 - 74 = 53

The element is Iodine and it's symbol is I.

However, The anion derived from the isotope has 54 electrons

A neutral Iodine should have 53 electrons. This means it has gained a single electron. The symbol is now written as;

I⁻

Answer:

Your answer is correct.

Explanation:

The steel paper clip would only move because it has steel in it, which is a magnetized material, plastic on the other side, is made up of polymers which are not attracted to the magnetic force, causing it not to move.

Explanation:

every object will remain at rest or in uniform motion in a straight line unless compelled to change its state by the action of an external force

Answer: Newton's 1st law of motion explains how things move and how forces work on their movement, which makes it an extremely important discovery.

Explanation: If we were to place an object into space, we could observe how it behaves without any external influences.

Moles of PF₃ : 4

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

[tex]\tt P_4(s)+6F_2(g)\rightarrow 4PF_3(g)[/tex]

1.25 moles of P₄(s) is reacted with 6 moles of F₂(g)

Limiting reactant : the smallest ratio (mol divide by coefficient)

P₄ : F₂ =

[tex]\tt \dfrac{1.25}{1}\div \dfrac{6}{6}=1.25\div 1\rightarrow F_2~limiting~reactant(smallest~ratio)[/tex]

mol PF₃ based on mol of limiting reactant(F₂), so mol PF₃ :

[tex]\tt \dfrac{4}{6}\times 6~moles=4~moles[/tex]

Answer:

C

Explanation:

In the bone marrow, red blood cells are produced

Answer:

The value is   [tex]k = 2 \ ppb[/tex]

Explanation:

From the question we are told that

   The volume of the drinking water is  [tex]V = 500 \ mL = 500 *10^{-3} \ L = 500 *10^{-6} \ m^3[/tex]

   The mass of  mercury it contains  [tex]m_c = 0.001 \ mg = 0.001 *10^{-3} \ g = 0.001 *10^{-6}\ kg[/tex]

Generally the mass of water is mathematically represented as

       [tex]m = V * \rho[/tex]

Here [tex]\rho[/tex] is the  density of water with value  [tex]\rho = 1000 \ kg/m^3[/tex]

So

       [tex]m = 500 *10^{-6 }* 1000[/tex]

=>    [tex]m = 0.5 \ kg[/tex]

Generally  ppb mean part per billon ,  and  1 billon is  100,000,000

So the part per billon which this represents is mathematically represented as

        [tex]k = \frac{0.001 *10^{-6}}{ 0.5} * 100 000 000[/tex]

=>     [tex]k = 2 \ ppb[/tex]

Answer:

2 ppb

Explanation:

I got it right in class!

Hope this Helps!! :))

Answer: Atoms are not able to exist independently

Explanation:

Answer:

0.53 mol NaCl

General Formulas and Concepts:

Chemistry - Atomic Structure

Explanation:

Step 1: Define

3.2 × 10²³ atoms NaCl

Step 2: Identify Conversions

Avogadro's number

Step 3: Convert

[tex]3.2 \cdot 10^{23} \ atoms \ NaCl(\frac{1 \ mol \ NaCl}{6.022 \cdot 10^{23} \ atoms \ NaCl} )[/tex] = 0.531385 mol NaCl

Step 4: Check

We are given 2 sig figs. Follow sig fig rules and round.

0.531385 mol NaCl ≈ 0.53 mol NaCl

Answer:

I think it is true you should go for true

Answer:B

Explanation:Because when the object heats up the particles move faster and it will turn into a liquid or gas but if it is being cooled then the particles will slow down and either make a liquid or solid.

Answer:

Posses both metal and non metal property

This question most likely has answer choices. The answer choices are as follows:

The answer is Metalloids are semiconductive (2nd option).

Answer:

C help stop bleeding

Explanation:

Platelets stop bleeding by clumping and forming plugs in blood vessel injuries

Answer:

0.288 mole of Fe.

Explanation:

We'll begin by calculating the number of mole present in 23.00g of iron(III) oxide (Fe2O3). This can be obtained as follow:

Mass of Fe2O3 = 23 g

Molar mass of Fe2O3 = (56×2) + (16×3)

= 112 + 48

= 160 g/mol

Mole of Fe2O3 =?

Mole = mass /Molar mass

Mole of Fe2O3 = 23 / 160

Mole of Fe2O3 = 0.144 mole

Next, we shall write the balanced equation for the reaction. This is given below:

2Al + Fe2O3 —> Al2O3 + 2Fe

From the balanced equation above,

1 mole of Fe2O3 reacted to produce 2 moles of Fe.

Finally, we shall determine the number of mole of Fe produced by the reaction of 23 g (i.e 0.144 mole) of Fe2O3. This can be obtained as illustrated below:

From the balanced equation above,

1 mole of Fe2O3 reacted to produce 2 moles of Fe.

Therefore, 0.144 mole of Fe2O3 will react to produce = 0.144 × 2 = 0.288 mole of Fe.

Thus, 0.288 mole of Fe is obtained from the reaction.

Answer:

Law of conservation of matter

Explanation:

Answer:

when you use energy , the total amount of energy decreases.

Answer:

The picture?

Explanation:

Please the picture

This makes no sence. Please put the picture up for us to answer. Thanks!

Answer:

a) 0.13 bar

b) 5.05 L

Explanation:

Let us take the mass of the mixture to be 100 g. Hence, 70% by weight of dioxygen corresponds to 70 g

Mass of dihydrogen = 100g - 70 g = 30g

Number of moles of dioxygen = 70g/32 g/mol = 2.2 moles of dioxygen

Number of moles of dihydrogen = 30g/2g/mol = 15 moles of dihydrogen

Total number of moles = 2.2 + 15 = 17.2 moles

Mole fraction of dioxygen = 2.2/17.2 = 0.13

Partial pressure = mole fraction * total pressure

Partial pressure of dioxygen = 0.13 * 1 = 0.13 bar

ii) number of moles in 8.8 g of CO2 = 8.8g/44g/mol = 0.2 moles

T = 31.1 + 273 = 304.1 K

P = 1 bar

V= ?

R = 0.083 bar L K-1 mol-1

From

PV=nRT

V = nRT/P

V= 0.2 * 0.083 * 304.1/1

V= 5.05 L

Answer its Ccccccccccccccccccccccccc