What is 72.9 g HCI into moles

Answer:

(B. Plants and meat)

Explanation:

Answer: 445.15 kJ of heat could be obtained by the combustion of 8.0 grams [tex]CH_4[/tex]

Explanation:

To calculate the moles :

[tex]\text{Moles of solute}=\frac{\text{given mass}}{\text{Molar Mass}}[/tex]    

[tex]\text{Moles of} CH_4=\frac{8.0g}{16.04g/mol}=0.50moles[/tex]

The given thermochemical equation is:

[tex]CH_4(g)+2O_2(g)\rightarrow CO_2(g)+2H_2O(g)[/tex]  [tex]\Delta H=890.3kJ[/tex]

According to stoichiometry :

1 mole of [tex]CH_4[/tex] on combustion produce heat = 890.3 kJ

Thus 0.50 moles of [tex]CH_4[/tex] on combustion produce heat =[tex]\frac{890.3}{1}\times 0.50=445.15kJ[/tex]

Thus 445.15 kJ of heat could be obtained by the combustion of 8.0 grams [tex]CH_4[/tex]

Answer: 34 gram of chromium produced from 50g of [tex]Cr_2O_3[/tex]

Explanation:

To calculate the moles :

[tex]\text{Moles of solute}=\frac{\text{given mass}}{\text{Molar Mass}}[/tex]    

[tex]\text{Moles of} Cr_2O_3=\frac{50g}{152g/mol}=0.33moles[/tex]

The decomposition of [tex]Cr_2O_3[/tex] follows the equation :

[tex]2Cr_2O_3\rightarrow 4Cr+3O_2[/tex]  

According to stoichiometry :

2 moles of [tex]Cr_2O_3[/tex] produce = 4 moles of [tex]Cr[/tex]

Thus 0.33 moles of [tex]Cr_2O_3[/tex] will produce=[tex]\frac{4}{2}\times 0.33=0.66moles[/tex]  of [tex]Cr[/tex]

Mass of [tex]Cr=moles\times {\text {Molar mass}}=0.66moles\times 52g/mol=34g[/tex]

Thus 34 gram of chromium produced from 50g of [tex]Cr_2O_3[/tex]

Answer:

The answer is decline and apparent

Explanation:

I took the test and got it right

Answer:

D 2,2

Explanation:

We can see that there are 2 chlorines on the reactant side so there has to be a 2 on the product side

Now we have Na + Cl2 --> 2NaCl

The problem now is that there are 2 sodiums on the product side so add a 2 to the Na on the reactant side

2Na + Cl2 --> 2NaCl

Now it's balanced!

Answer:

3.94 L

Explanation:

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

Mass of O₂ = 5.62 g

Volume of O₂ =?

Next, we shall determine the number of mole present in 5.62 g of O₂. This can be obtained as follow:

Mass of O₂ = 5.62 g

Molar mass of O₂ = 2 × 16 = 32 g/mol

Mole of O₂ =?

Mole = mass / molar mass

Mole of O₂ = 5.62 / 32

Mole of O₂ = 0.176 mole

Finally, we shall determine the volume of 5.62 g (i.e 0.176 mole) of O₂ at STP. This can be obtained as follow:

1 mole of O₂ occupied 22.4 L at STP.

Therefore, 0.176 mole of O₂ will occupy = 0.176 × 22.4 = 3.94 L at STP.

Thus 5.62 g (i.e 0.176 mole) of O₂ occupied 3.94 L at STP

Answer:

6.60 moles of ZnO have 537,108 g.

Explanation:

Answer:

Average atomic mass = 19.9 amu

Explanation:

Isotopes can be defined as two or more forms of a chemical element that are made up of equal numbers of protons and electrons but different numbers of neutrons.

Generally, the isotopes of a chemical element have the same chemical properties because of their atomic number but different physical properties due to their atomic weight (mass number).

Given the following data;

Relative abundance of Z-19 = 55%

Relative abundance of Z-21 = 45%

Atomic mass of Z-19 = 19 amu

Atomic mass of Z-21 = 21 amu

To find the average atomic mass;

Average atomic mass = 19 * (55/100) + 21 * (45/100)

Average atomic mass = 19*0.55 + 21*0.45

Average atomic mass = 10.45 + 9.45

Average atomic mass = 19.9 amu

Therefore, the average atomic mass for element Z is 19.9 amu.

3.44 × 10⁻¹⁰ g Pb

Math

Pre-Algebra

Order of Operations: BPEMDAS

Chemistry

Atomic Structure

Stoichiometry

Step 1: Define

[Given] 1.00 × 10¹² atoms Pb

[Solve] grams Pb

Step 2: Identify Conversions

Avogadro's Number

[PT] Molar Mass of Pb - 207.2 g/mol

Step 3: Convert

Step 4: Check

Follow sig fig rules and round. We are given 3 sig figs.

3.44072 × 10⁻¹⁰ g Pb ≈ 3.44 × 10⁻¹⁰ g Pb

Answer:

[tex]\boxed {\boxed {\sf 3.44 *10^{-10} \ g \ Pb}}[/tex]

Explanation:

1. Atoms to Moles

Use Avogadro's Number to convert atoms to moles. This number: 6.022*10²³, tells us the number of particles (atoms, molecules, etc.) in 1 mole of a substance. In this case, the particles are atoms of lead.

[tex]\frac {6.022*10^{23} \ atoms \ Pb}{1 \ mol \ Pb}[/tex]

Multiply by the given number of atoms.

[tex]1.00 *10^{12} \ atoms \ Pb *\frac {6.022*10^{23} \ atoms \ Pb}{1 \ mol \ Pb}[/tex]

Flip the fraction so the atoms of lead cancel.

[tex]1.00 *10^{12} \ atoms \ Pb *\frac {1 \ mol \ Pb}{6.022*10^{23} \ atoms \ Pb}[/tex]

[tex]1.00 *10^{12}*\frac {1 \ mol \ Pb}{6.022*10^{23}}[/tex]

[tex]\frac {1.00 *10^{12}\ mol \ Pb}{6.022*10^{23}} = 1.66057788*10^{-12} \ mol \ Pb[/tex]

2. Moles to Grams

Use the molar mass to convert moles to grams. This can be found on the Periodic Table. For lead it is 207.2 grams per mole.

[tex]\frac {207.2 \ g\ Pb}{ 1 \ mol \ Pb}[/tex]

Multiply by the number of moles we calculated.

[tex]1.66057788*10^{-12} \ mol \ Pb* \frac {207.2 \ g\ Pb}{ 1 \ mol \ Pb}[/tex]

[tex]1.66057788*10^{-12}* \frac {207.2 \ g\ Pb}{ 1 }[/tex]

[tex]1.66057788*10^{-12}* {207.2 \ g\ Pb}= 3.44071737*10^{-10} \ g \ Pb[/tex]

3. Round

The original measurement of atoms has 3 significant figures, so our answer must have the same. For the number we calculated, it is the hundredth place. The 0 in the thousandth place tells us to leave the 4.

[tex]3.44 *10^{-10} \ g \ Pb[/tex]

Answer: 12.1 ml of ethanol is needed

Explanation:

To calculate the moles :

[tex]\text{Moles of solute}=\frac{\text{given mass}}{\text{Molar Mass}}[/tex]    

[tex]\text{Moles of} CO_2=\frac{18.2g}{44g/mol}=0.414moles[/tex]  

[tex]C_2H_5OH(l)+3O_2(g)\rightarrow 2CO_2(g)+3H_2O(l)[/tex]  

According to stoichiometry :

2 moles of [tex]CO_2[/tex] is produced by = 1 mole of [tex]C_2H_5OH[/tex]

Thus 0.414 moles of [tex]CO_2[/tex] is produced by=[tex]\frac{1}{2}\times 0.414=0.207moles[/tex]  of [tex]C_2H_5OH[/tex]

 Mass of [tex]C_2H_5OH=moles\times {\text {Molar mass}}=0.207moles\times 46.07g/mol=9.54g[/tex]

Volume of ethanol = [tex]\frac{\text {Mass of ethanol}}{\text {density of ethanol}}=\frac{9.54g}{0.789g/ml}=12.1ml[/tex]

12.1 ml of ethanol is needed to produce 18.2 g of [tex]CO_2[/tex]

Answer:

it is true because if you subtract 10 - 14 you will get -4 so it is less than 107.

Explanation:

Hope this helps!

Answer:

The answer is c. A + BC → AC + B

Answer:

5.43×10¯³² J

Explanation:

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

Wavelength (λ) = 3.66×10⁴ hm

Energy (E) =?

Next, we shall convert 3.66×10⁴ hm to metre (m). This can be obtained as follow:

1 hm = 100 m

Therefore,

3.66×10⁴ hm = 3.66×10⁴ hm × 100 m / 1 hm

3.66×10⁴ hm = 3.66×10⁶ m

Next, we shall determine the frequency of the frequency of the photon. This can be obtained as follow:

Wavelength (λ) = 3.66×10⁶ m

Velocity (v) = 3×10⁸ m/s

Frequency (f) =?

v = λf

3×10⁸ = 3.66×10⁶ × f

Divide both side by 3.66×10⁶

f = 3×10⁸ / 3.66×10⁶

f = 81.97 Hz

Finally, we shall determine the energy of the photon. This can be obtained as follow:

Frequency (f) = 81.97 Hz

Planck's constant (h) = 6.63×10¯³⁴ Js

Energy (E) =?

E = hf

E = 6.63×10¯³⁴ × 81.97

E = 5.43×10¯³² J

Therefore, the energy of the photon is 5.43×10¯³² J

1100 mmHg

Math

Pre-Algebra

Order of Operations: BPEMDAS

Chemistry

Gas Laws

Stoichiometry

Step 1: Define

[Given] 1.5 atm

[Solve] mmHg

Step 2: Identify Conversions

1 atm = 760 mmHg

Step 3: Convert

Step 4: Check

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

1140 mmHg ≈ 1100 mmHg

Answer:

c. 2s2 2p5

Explanation:

2s2 2p5 has 7 valence electrons and only needs one electron to complete the octet.  This element will be the most electronegative.

Answer:

N2 (nitrogen) O3 (ozone) CaO (calcium oxide) C6H12O6 (glucose, a type of sugar)

Answer:

dihydrogen monoxide

dinitrogen monosulfide

Answer:

A) actual yield

Explanation:

Theoretical yield is the amount of product expected based on the stoichiomety.

Percent yield is the actual yield over the theoretical yield.

Answer:

Metal + Oxygen -> Metal Oxide

Explanation:

It's pretty self-explanatory. However, let me show you an example:

Iron + Oxygen -> Iron Oxide

Iron rusts. When iron rusts, it comes in contact with air to form Iron Oxide, which is rust itself.

Answer:

Option F 6 will be the answer.

Answer:

Iron (II) sulfide and oxygen

Answer:

0.009

Explanation:

Molarity, a measure of molar concentration of a substance is calculated thus;

Molarity = number of moles ÷ volume

According to the provided information, mass of KCl = 0.47g, volume of water = 700ml

Using mole = mass/molar mass

Molar Mass of KCl = 39.10 + 35.453

= 74.553g/mol

Mole = 0.47/74.55

Mole = 0.0063mol

Volume of water = 700ml = 700/1000 = 0.7L

Molarity = 0.006/0.7

Molarity = 0.00857

The value of molarity rounded to three decimal places (3 d.p) = 0.009

Explanation:

The equation of the reaction is given as;

Be + 2HCl → BeCl2 + H2

What is the mass of beryllium required to produce 25.0g of beryllium chloride?

1 mol of Be produces 1 mol of BeCl2

Converting to mass;

Mass = Molar mass  *  Number of moles

9.01g of Be produces 79.92g of BeCl2

xg of Be produces 25g of BeCl2

Solving for x;

x = 25 * 9.01 / 79.92

x = 2.82 g

What is the mass of hydrochloric acid required to produce 25.0g of beryllium chloride? g

Converting 25.0g of beryllium chloride to moles;

Number of moles = Mass / Molar mass

Number of moles = 25 / 79.92 = 0.3128 mol

2 mol of HCl produces 1 mol of BeCl2

x mol of HCl would produce 0.3128 mol of BeCl2

solving for x;

x = 0.3128 * 2 = 0.6256 mol

Converting to mass;

Mass = 0.6256 * 36.5 = 22.83 g

What is the mass of hydrogen gas produced when 25.0g of beryllium chloride is also produced? g

25g of BeCl2 = 0.3128 mol of BeCl2

From the equation;

1 mol of H2 is produced alongside 1 mol of BeCl2

This means;

0.3128 mol of H2 would also be produced alongside 0.3128 mol of BeCl2

Mass = Number of moles * Molar mass

Mass = 0.3128mol * 2.0159 g/mol = 0.6306 g

Answer:

Increases, decreases

Explanation:

Answer:

a

Explanation:

the line is going down

To determine the highest angle the pendulum will swing to after the impact, we can apply the principle of conservation of momentum. Initially, the total momentum is zero since the pendulum is at rest.

After the impact, the total momentum remains zero because the block and embedded projectile move together as a single system.First, let's convert the weight units to a common system. The 5-pound rod is approximately 2.27 kg, and the 10-pound wooden block is around 4.54 kg. The projectile's weight is 0.3 oz, which is about 0.0085 kg.The momentum before the impact is zero, so the momentum after the impact must also be zero. This can be expressed as:(2.27 kg + 4.54 kg + 0.0085 kg) * V_final = 0Solving for V_final gives us V_final ≈ 0 ft/s. Since the velocity is zero after the impact, the pendulum will momentarily stop at its highest point.Therefore, the highest angle the pendulum will swing to after the impact is 0 degrees, or it will come to rest at the vertical position.

Learn more about momentum here :

https://brainly.com/question/30677308

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(I leave off the x10^23 because they both will divide out)    Use your per

Answer:

The cytoplasm of erythrocytes is rich in hemoglobin, an iron-containing biomolecule that can bind oxygen and is responsible for the red color of the cells and the blood. Each human red blood cell contains approximately 270 million of these hemoglobin molecules.

Explanation:

hope this helps(;