what was the control group for this experiment?

Answer:

A. 36 percent recieved Bs

B. 40 percent of students received Cs

Explanation:

Amount of students: 12+18+20=50

Students with Bs: (18÷50) x 100 = 36%

Students with C's: (20÷50) x100 = 40%

On the first chemistry test 12 students got A, 18 students got B, and 20 student got C. Thus the percentage of students received B is 0.36 and percentage of students received c is 0.40

In mathematics, a number or ratio expressed as a fraction of 100. It is often denoted using the percent sign %. A percentage is a dimension less unit and it has no unit.

In above question 12 student got A, 18 student got B, and 20 student got C.

So total number of student = 12 + 18 + 20 = 50.

Then the percentage of students received B is as follows:-

Percentage of students who got B = (student who got B/Total number of student) X 100.

=(18/50) X 100

= 36%

Now percentage of students who got C = (No of students who got C/Total students)X100

=(20/50) X 100

=40%.

Therefore,On the first chemistry test 12 students got A, 18 students got B, and 20 student got C. Thus the percentage of students received B is 0.36 and percentage of students received c is 0.40 percentage of students who got B is 36% and percentage of students who got C is 40%

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Answer:

Los alimentos para evitar la fatiga durante una carrera son alimentos bajos en grasas y altos en carbohidratos, así como alimentos bajos en fibra como pan, mantequilla de maní, plátano, jugo de frutas sin pulpa, y beber hasta aproximadamente 600 ml de líquido aproximadamente 3 horas. antes de la carrera

La comida para comer unos días antes de la carrera incluye carnes magras, arroz, pasta y verduras con contenido de almidón.

Los alimentos que se deben evitar incluyen carne roja, alimentos con alto contenido de grasas saturadas, alimentos fritos, pasteles y salchichas.

Explanation:

Answer:

Determine the volume of helium gas

Answer:

About 1,495 Liters of Helium.

Explanation:

To calculate the volume of helium gas formed when the magnet loses its superconducting properties, we can use the ideal gas law:

PV = nRT

Where:

P = Pressure (in atm)

V = Volume (in liters)

n = Number of moles of helium gas

R = Ideal gas constant (0.0821 L.atm/(mol.K))

T = Temperature (in Kelvin)

First, we need to find the number of moles of helium gas:

Given volume of liquid helium (V_liquid) = 1950 L

Density of liquid helium (ρ) = 0.125 g/mL = 0.125 g/cm³

To convert density from g/cm³ to g/L, we multiply by 1000:

Density of liquid helium (ρ) = 0.125 g/cm³ * 1000 cm³/L = 125 g/L

Mass of liquid helium (m) = Volume * Density = 1950 L * 125 g/L = 243,750 g

Next, we need to convert the mass of liquid helium to moles using the molar mass of helium:

Molar mass of helium (M) = 4.0026 g/mol

Number of moles (n) = Mass / Molar mass = 243,750 g / 4.0026 g/mol ≈ 60,907 mol

Now, we have the number of moles of helium gas (n), and we can calculate the volume of helium gas (V_gas) at 25°C (298.15 K) and 1 atm:

P = 1 atm

T = 25°C = 298.15 K

V_gas = nRT / P

V_gas = (60,907 mol) * (0.0821 L.atm/(mol.K)) * (298.15 K) / (1 atm)

V_gas ≈ 1,495 L

Therefore, approximately 1,495 liters of helium gas would be formed at 25°C and 1 atm when the magnet loses its superconducting properties.

Answer:

natural resources: materials or substances such as minerals, forests, water, and fertile land that occur in nature and can be used for economic gain.

renewable resources:  a natural resource that is unlimited or that is naturally replenished rather quickly, such as sunlight or water

non renewable resources: (also called a finite resource) is a natural resource that cannot be readily replaced by natural means at a pace quick enough to keep up with consumption.

Answer:

Common diatomic molecules include hydrogen (H2), nitrogen (N2), oxygen (O2), and carbon monoxide (CO). Seven elements exist as homonuclear diatomic molecules at room temperature: H2, N2, O2, F2, Cl2, Br2, and I2. The bond in a homonuclear diatomic molecule is non-polar due to the electronegativity difference of zero.

Answer:

Cation metal. Positive charge.

Answer:

DHS has been working hard for years and it is still unclear whether this would happen if it is to end the market with the engine is a little less than the next 5years to be 8years in the first quarter and the same year in a quarter or less than a quarter or more than that

Answer:

For example, the bond between the sodium and chlorine atoms in sodium chloride (NaCl) is formed by the transfer of an electron from sodium to chlorine, creating Na + and Cl – ions. ... The electrostatic attraction between these ions provides the bonding in NaCl.

Two metals with equal mass will absorb heat according to their heat absorbing capacity.

The increase in entropy will cause the solid substance to break into multiple pieces.

When these solute particles detach from each other they will form a solution. Entropy increase will cause the temperature to increase.

Decrease in enthalpy is an exothermic reaction which releases heat from the reaction and then desired products will be formed.

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The first shell can only hold 2 electrons, but the pupil placed in 8 electrons.

The second shell can hold up to 8 electrons, but the pupil only placed in 2 electrons.

Flourine only has 9 total electrons, yet there are 10 electrons in the diagram.

Answer:

Explanation:

In the Fluorine atom there are 2 electrons in the innermost shell and 7 i the outer shell.

Answer:

58.44 g/mol

Explanation:

58.44 g/mol

Answer:

b is the correct answer ok

A solution is made up of solute and solvent. It is an addition of two or more substances to each other that combines physically and chemically. Thus, option B is correct.

A solution is the mixture of solutes that can be more than one in a solvent that has the same composition all over (homogenous). A solution comprises two main elements called a solute and a solvent.

A solute is the part of the solution that has been added to the solvent for desolvation. On the other hand, the solvent is the substance that dissolves the solute in them to make a solution.

The homogenous mixture or the solution can be created by mixing salt and water, sugar and water, mercury in amalgamated zinc, coffee, vinegar, etc.

Therefore, option B. a solution is the addition of the substances that combine physically.

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Answer:

it means air pollution Environment. The chemicals and nutrients found in fertilizers, while beneficial for agricultural crops, can be lethal in high doses for fish, birds and other wildlife. Pesticides, designed to kill pests chemically, are also dangerous when leached into soil or groundwater supplies.

Answer:

C A B

Explanation:

come on, you also know this from normal water waves.

which ones are stronger (= have more energy) ? the small ones or the big ones ?

and the same applies to all waves. the bigger the waves (higher amplitude), the more energy.

Answer:

The correct answer is - not very effective; forewarning tends to reduce the effectiveness of an attitude change

Explanation:

The strategy of forewarning or warning before attempting any change in the psychology of an individual is found to be less effective. The subject sees a  forewarning seen as a warning that a person is going to attempt to make changes in the attitude of a person about a particular thing or situation.

As a result, the person is ready to defenses up with regard to that idea of persuasion which Builds up defenses for the situation. Therefore, the effect of persuasion is reduced on the person.

Thus, Matty's strategy is not very effective; forewarning tends to reduce the effectiveness of an attitude change

Answer:

D

Explanation:

The correct answer would be that the thermal energy of the sun is transferred to the pavement.

Thermal energy refers to the internal energy possessed by a system by virtue of the movement of molecules within such a system. In other words, it is the heat energy possessed by a system.

When the thermal energy from the sun warms the pavement, it means that the thermal energy from the sun has been successfully transferred to the pavement. Thermal energy can be transferred by conduction, convection, or by radiation depending on whether the system is a solid, liquid, gas respectively.

The correct option is, therefore, D.

Answer:

C

Explanation:

C. Adding a catalyst would increase the reaction rate.

A catalyst is a substance that increases the rate of a chemical reaction by lowering the activation energy required for the reaction to occur.

A catalyst enhances the probability of successful collisions between reactant molecules, which raises the pace of the reaction by offering an additional avenue for the reaction to occur.

As there would be fewer reactant molecules accessible to react with one another, decreasing reactant concentrations would result in a slower pace of reaction.

Due to the fact that chemical reactions often require energy to take place, eliminating heat from the system would also slow down the reaction rate. A lower value for k would result in a lower rate constant, which would lower the response rate.

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Explanation:

a chemical reaction in which the rate of reaction is proportional to the concentration of each of three reacting molecules

The reaction is the formation of the product from the reactants. A reaction happens quickest during the beginning of the reaction. Thus, option A is correct.

The reaction rate is the pace at which the reaction takes place and the breakdown or the combination of the reactants to produce the products. The rate of reaction depends on the concentration of the reactants.

The concentration of the reactants is in direct proportion with the rate as at the beginning of a reaction there is a higher amount of substance present than at the end.

As the reaction proceeds, the reactants get consumed and their concentration decreases. As there is a decrease in concentration the rate of the reaction converting and producing the products also decreases.

Therefore, option. the rate of reaction is fast at the beginning.

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Answer:

N=35%. so 35/100*7 =2.45%

H=5.0 so 5/100*1=0.05%

o=60% so 60/100*8=4.8%

Answer:

D

Explanation:

Hypotheses are educated guesses, and the best answer is the one with an if, as it indicates that it's a guess.

Answer:

letter b should be the answer

Answer:

The melting point determination may need improvement- it may not have been done properly, and make sure it was repeated at least once.

Explanation:

Given that we know the actual melting point of pure acetylsalicyclic acid to be 135°, it follows that the process followed to obtain the melting point range of 114 to 125 degrees Celsius must be inaccurate.

Therefore, we can conclude that, the melting point determination may need improvement. It may not have been done properly, and we must make sure it is repeated at least once.

Answer:

the correct answer is option ( A )

Both A and R are true and R is the correct explanation of A.

Explanation:

hope it helps you

Mark my answer as brainlist

have a nice day

Answer:

1. 2.63x10^6

2. 39.2

Both answers have been rounded

Answer:

Movement of water from the area of high concentration of solute to the area of low concentration of solute.

Explanation:

Diffusion can be defined as the movement of gas molecules from a region of high concentration to a region of lower concentration until an equilibrium is attained or reached. This mixing of gas molecules in the liquid or gaseous state is due to their kinetic energy of random motion i.e without requiring bulk motion.

This ultimately implies that, diffusion is a phenomenon through which gas molecules in either a gaseous or liquid state spread out in response to a concentration gradient, which is simply the difference in concentration of the gases across a space.

During diffusion, molecules move from areas of high concentration to areas of low concentration. Also, diffusion does not require energy to move molecules.

Hence, the process of diffusion can be described as movement of water from the area of high concentration of solute to the area of low concentration of solute.

A solute can be defined as a substance that is typically dissolved in a liquid solvent such as water, coffee, tea, etc., to produce a solution.

Answer:

1 Anomalous Pairs. The rest of the  pairs of elements don't follow the follow Mendeleev's Principles . they are :

2Grouping of chemically dissimilar elements.  

3Position of Isotopes.  

4Electronic arrangement.  

5Separation of chemically similar elements.  

6The position of hydrogen.

You're going to first balance the chemical equation.

After that, convert the grams of Na into moles of Na, and then multiply that with the ratio of moles of NaCl to Na, and then convert the mol of NaCl into grams in order to obtain the theoretical yield, since we are given that Na is the limiting reactant.

After that, plug the values into the yield formula, doing some basic algebra, and you should get your result.

You're going to first balance the chemical equation.

After that, convert the grams of Na into moles of Na, and then multiply that with the ratio of moles of NaCl to Na, and then convert the mol of NaCl into grams in order to obtain the theoretical yield, since we are given that Na is the limiting reactant.

After that, plug the values into the yield formula, doing some basic algebra, and you should get your result.

Answer:

chlorate=Acid

peroxide=Acid

silver=Acid

zinc= Basic

nitrite=Acid

Answer:

His rule states that if a cyclic, planar molecule has 4n+2 π electrons