I really need help on this question please help

Answer:

A. cementation

Explanation:

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Answer:

It’s probably plants seed and raise crops for their food

Explanation:

Answer:

I would say b

Explanation:

A hunter would go out to hunt and gathers handle crops or find crops so b.

Answer:

Option D. 3 ppm isopropanol

Explanation:

The following data were obtained from the question:

Mass of isopropanol = 6 mg

Mass of water = 2 Kg

Isopropanol concentration =?

The isopropanol concentration can be obtained as follow:

Concentration = mass isopropanol / mass of water

Isopropanol concentration = 6 mg / 2 kg

Isopropanol concentration = 3 mg/Kg

Finally, we shall convert 3 mg/Kg to ppm. This can be obtained as follow:

1 mg/Kg = 1 ppm

Therefore,

3 mg/Kg = 3 ppm

Thus, we can conclude that the concentration of isopropanol is 3 ppm.

Answer:  [tex]2C_{12}H_{26}(l)+37O_2(g)\rightarrow 24CO_2(g)+26H_2O(g)[/tex]

2.  369 L

Explanation:

1. Combustion is a chemical reaction in which hydrocarbons are burnt in the presence of oxygen to give carbon dioxide and water.

The balanced chemical reaction is:

[tex]2C_{12}H_{26}(l)+37O_2(g)\rightarrow 24CO_2(g)+26H_2O(g)[/tex]

2. To calculate the moles, we use the equation:

[tex]\text{Number of moles}=\frac{\text{Given mass}}{\text {Molar mass}}=\frac{220g}{170.3g/mol}=1.29moles[/tex]

According to stoichiometry :

2 mole of dodecane produces = 24 moles of carbon dioxide

Thus 1.29 moles of dodecane produces = [tex]\frac{24}{2}\times 1.29=15.5 moles[/tex] of carbon dioxide

According to ideal gas equation:

[tex]PV=nRT[/tex]

P = pressure of gas = 1 atm

V = Volume of gas = ?

n = number of moles = 15.5

R = gas constant =[tex]0.0821Latm/Kmol[/tex]

T =temperature =[tex]17^0C=(17+273)K=290K[/tex]

[tex]V=\frac{nRT}{P}[/tex]

[tex]V=\frac{15.5\times 0.0821L atm/K mol\times 290K}{1atm}=369L[/tex]

Thus the volume of carbon dioxide gas that is produced is 369 L

Hope this helps!!

Thank You!

Answer:

Explanation:

The molecular formula for Guanylate is [tex]\mathbf{C_{10} H_{14} N_5O_8 P}[/tex]

This is calculated by the addition of the atomic weight of all the atoms taking part in the molecule.

i.e. (10 × C) +  (14 × H) + (5 × N) + ( 8 × O) + (1 × P)

= (10 × 12) +  (14 × 1) + (5 × 14) + ( 8 × 16) + (1 × 30)

= 120 + 14 + 70 + 128 + 30

= 362 g/mol

The diagram for the tautomers of hypoxanthine can be seen in the image attached below.

Dihydrouridine is available and can be seen in tRNAs and rRNAs. It is an exceptionally preserved and adjusted base. It is a pyrimidine nucleoside that is shaped by the expansion of two hydrogen atoms to uridine. By the expansion of two hydrogen atoms to uridine makes it completely soaked and no presence of any two-fold or double bond.  

Catalytic reduction of carbon-carbon double bonds in Dihydrouridine synthase occurs at positions 5 and 6 on the uridine base.  

Hence, 5 and 6 carbon particles inside the uracil moiety of this nucleotide have two hydrogens each connected to them.

Answer:

13414 years

Explanation:

From;

0.693/ t1/2 = 2.303/t log No/N

t1/2 = half life of  C-14

t = age of the sample

No= initial amount of C-14

N = present amount of C-14

From the question, N = 0.2 No

Hence;

0.693/5700 = 2.303/t log No/0.2No

1.2 * 10^-4 = 2.303/t log 1/0.2

1.2 * 10^-4 = 1.6097/t

t = 1.6097/1.2 * 10^-4

t = 13414 years

Answer:

Conductor is any material tht allows he flow of electrons or electric current . Ex: Metals like iron and copper.

Hope im right!!

Answer:-

Answer:

temperature

Explanation:

hope this helps

Answer: Echinoderms usually have five appendages (arms or rays), but there are some exceptions. Radial symmetry means that the body is a hub, like a bicycle wheel, and tentacles are spokes coming out of it (think of a starfish).

Explanation:

Answer:

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Explanation:

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Answer:

1. Percentage yield is 64.75%

2. Atom economy is 48.39%

Explanation:

1. Determination of the percentage yield

Experimental yield = 24.8 g

Theoretical yield = 38.3 g

Percentage yield =?

Percentage yield = Experimental yield /Theoretical yield × 100

Percentage yield = 24.8 / 38.3 × Percentage yield = 2480 / 38.3

Percentage yield = 64.75%

2. Determination of the atom economy.

The balanced equation for the reaction is given below:

6CO₂ + 6H₂O —> C₆H₁₂O₆ + 6O₂

Next, we shall determine the mass of CO₂, H₂O and C₆H₁₂O₆ from the balanced equation.

Molar mass of CO₂ = 12 + (16×2)

= 12 + 32

= 44 g/mol

Mass of CO₂ from the balanced equation = 6 × 44 = 264 g

Molar mass of H₂O = (2×1) + 16

= 2 + 16

= 18 g/mol

Mass of H₂O from balanced equation = 6 × 18 = 108 g

Molar mass of C₆H₁₂O₆ = (6×12) + (12×1) + (6×16)

= 72 + 12 + 96

= 180 g/mol

Mass of C₆H₁₂O₆ from the balanced equation = 1 × 180 = 180 g

Next, we shall determine the total mass of the reactants. This is illustrated below:

Mass of CO₂ = 264 g

Mass of H₂O = 108 g

Total mass of reactants =?

Total mass of reactant = Mass of CO₂ + Mass of H₂O

Total mass of reactant = 264 + 108

Total mass of reactant = 372 g

Finally, we shall determine the atom economy. This can be obtained as follow:

Mass of desire atom (C₆H₁₂O₆) = 180 g

Total mass of reactants = 372 g

Atom economy =.?

Atom economy = mass of desire atom / total mass of reactant × 100

Atom economy = 180/372 × 100

Atom economy = 48.39%

Answer:

a) 0.714g of bicarbonate of soda are required.

b) 0.221g of Al(OH)₃ are required

Explanation:

The reactions of HCl with bicarbonate of soda and aluminium hydroxide are:

HCl + NaHCO₃ → H₂O + NaCl + CO₂

3 HCl + Al(OH)₃ → 3H₂O + AlCl₃

The moles of HCl that we need neutralize are:

50mL = 0.050L * (0.17mol / L) = 0.0085 moles HCl

To solve these problem we need to find the moles of the antacid using the chemical reaction and its mass using its molar mass;

a) Moles NaHCO₃ = Moles HCl = 0.0085 moles

The mass is -Molar mass NaHCO₃: -84g/mol-

0.0085 moles * (84g / mol) = 0.714g of bicarbonate of soda are required

b) 0.0085 moles HCl * (1mol Al(OH)₃ / 3mol HCl) = 2.83x10⁻³ moles Al(OH)₃

The mass is -Molar mass: 78g/mol-:

2.83x10⁻³ moles Al(OH)₃ * (78g/mol) =

Answer:

White blood cells are cells of the system, which play a neighborhood in protecting the body against infectious diseases and foreign bodies. These cells flow with the blood throughout the body then scavenge and kill the parasites and foreign bodies. Hence, they are called soldiers of the body.

I hope it's helpful!

Answer:

C. digestive; circulatory

Explanation:

It is the correct answer..

Answer: [tex]CaCO_3+2HCl\rightarrow CaCl_2+H_2O+CO_2[/tex]

Explanation:

Neutralization is a chemical reaction in which acid and base combine to form salt and water. Acids donate[tex]H^+[/tex] and bases donate [tex]OH^-[/tex]  in water which combine to form water molecules.

The chemical reaction between calcium carbonate and hydrochloric acid forms calcium chloride , water and carbon dioxide.

The balanced chemical equation is:

[tex]CaCO_3+2HCl\rightarrow CaCl_2+H_2O+CO_2[/tex]

Calcium also be called the calcium of citric acid because calcium citrate malate contains the calcium salt of citric acid and malic acid.

Citric acid is an organic compound with a chemical formula [tex]HOC(CO_2H)[/tex].

Calcium citrate malate is a water-soluble calcium supplement. It is the calcium salt of citric acid and malic acid with variable composition.

Hence, calcium is also called the calcium of citric acid.

Learn more about citric acid here:

https://brainly.com/question/11238674

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Answer: H2o

Explanation:

because oxygen is in the air

When the pressure of a sample of hydrogen gas increases from 760 torr to 860 torr, the expression D 760 / 860 represents the volume of hydrogen gas in liters.

Boyle's law is a law stating that the pressure of a given mass of an ideal gas is inversely proportional to its volume at a constant temperature.

A sample of hydrogen gas occupies 1.0 L at 760 torr in a balloon. We can calculate the volume when the pressure is increased to 860 torr using Boyle's law.

P₁ × V₁ = P₂ × V₂

V₂ = (P₁/P₂) × V₁

V₂ = (760 torr/860 torr) × 1.0 L = 0.88 L

where,

When the pressure of a sample of hydrogen gas increases from 760 torr to 860 torr, the expression D 760 / 860 represents the volume of hydrogen gas in liters.

Learn more about Boyle's law here: https://brainly.com/question/469270

Answer:

1/2

Explanation:

Half of 6 is 3 so therefore it is a half.

Answer:

Most Likely A High Pressure Center

Explanation:

is most likely high pressure Center because on a weather map over the southern western Pennsylvania there's mostly high pressure over there. The descending air diverges and spreads out from the center and their is a Coriolis effect which causes the Diverging air to rotate in a clockwise direction.

Answer:

6. solar eclipsis

7. drive less fuel efficient vehicles

Explanation:

these are the only questions i get but i still hope this helps :)

Answer:

Because The white gene is the recessive gene and the brown gene is the dominant gene hence all the offspring being brown instead of white :)

Explanation:

Thank me later!

Answer:

Explanation:What is the demand factor for three commercial ranges?

Answer:

Vaccines include a variety of ingredients including antigens, stabilizers, adjuvants, antibiotics, and preservatives. They may also contain residual by-products from the production process.

Answer:

hi

Explanation:

than you for points and thank me if you like

Answer:

The correct answer is -

1.  a) The bubbles will shrink, some may vanish.

2. a) Can A will make a louder and stronger fizz than can B.

Explanation:

In the first question, it is given that the bottle is not opened and therefore, squeezing the bottle filled with a carbonated drink will increase the pressure on the carbonated liquid which forces the bubbles to dissolve or displace or vanish as it moves to empty space.

Thus, the correct answer would be - The bubbles will shrink, some may vanish

In the second question, there are two different conditions for two different unopened cans of carbonated water that are different temperatures one at the garage with higher temperature and one in the fridge at low temperature. As it is known that higher the temperature less will be solubility of gas in liquid so gas in can A will be less soluble which means it has more gas and it will make louder and stronger fizz than B which was stored at low temperature.

thus, the correct answer would be - Can A will make a louder and stronger fizz than can B.

Answer: A) More base is likely required to reach the endpoint for the diprotic acid than for the monoprotic acid under these conditions

Explanation:

The monoprotic acid (HA) has a valency of 1 and diprotic acid  [tex](H_2A)[/tex] has a valency of 2.

As the concentration and volume of the diprotic acid and the monoprotic acids are equal.

The neutralization reaction for monoprotic acid is:

[tex]HA+BOH\rightarrow BA+H_2O[/tex]

The neutralization reaction for diprotic acid is:

[tex]H_2A+2BOH\rightarrow B_2A+2H_2O[/tex]

Thus more number of moles of base are required for neutralization of diprotic acid and thus the volume required will be more as concentration and volume of the diprotic acid and the monoprotic acids are equal.