A(n)_________ test only one factor at a time

Answer:

0.021 in scientific notation is 2.1 x 10^-2

Explanation:

Since there are two zeros before the non-zero digits, 10 should be raised to -2.

hope this helps

Using scientific notation, one can express extremely big or extremely small values. When a number between 1 and 10 is multiplied by a power of 10, the result is represented in scientific notation. 0.021 in scientific notation is 2.1 x 10⁻².

A way to express numbers that are either too large or too little to be conveniently stated in decimal form is through scientific notation. It is also known as "scientific form" in Britain, because scientists, mathematicians, and engineers frequently use it for intricate calculations involving large numbers.

A condensed manner of writing numbers is known as scientific notation (also known as standard form). A number is represented by a number from 1 to less than 10, multiplied by a power of 10, when it is written in scientific notation.

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Answer:

cd

Explanation:

image is formed due to reflected light rays and it is enlarged because image distance/ object distance = height of image/height of object

v>u so image is enlarged

Answer:

All right. So let's calculate the density of a glass marble. Remember that the formula for density is mass over volume. So if I know that the masses 18.5 g. And I know that the um volume is 6.45 cubic centimeters. I can go ahead and answer this to three significant figures. So it's going to be 2.87 grams per cubic centimeter. Okay, that's our density. Now, density is an intensive process. Okay. We're an intensive property. I really should say. It doesn't depend on how much you have. Mhm. If I have one marble, its density is going to be 2.87 g per cubic centimeter. If I have two marbles, the density will be the same because I'll double the mass and I'll also double the volume. So when I divide them I'll get the same number. Okay, that's what makes it an intensive property. No matter how many marbles I have, they'll have the same density. Mass though is not an intensive property. So if I have six marbles and I want to know what the massive six marbles is. Well, I know the mass of each marble is 18.5 g. So the mass of six marbles Is going to be 100 11 g. Because mass is an extensive property. It depends on how much you have. If I change the number of marbles, I'm going to change the mass. That's an extensive property. All right. So we've calculated the density. We've calculated the mass and then what happens to the density of one marble compared to six marbles as we mentioned before. Since densities and intensive property, the densities will be the same, no matter how may.

Explanation:

Answer: theo mình thì mình làm như sau

cu(no3)2 nhiệt phân hết

\Rightarrow nNO2= 0,02mol

nO2=0,005mol

khi hấp thụ O2 và NO2 vào nước ta có

2NO2 + 1/2 O2\Rightarrow 2HNO3

phản ứng là vừa đủ nên

nHNo3= 0,02 mol

pH HNO3=2

khi cho 0,001mol NaOH vào thì phản ứng trung hòa

H+ + OH- \Rightarrow H20

nHNO3=0,02/20=0,001

nhận thấy nH+ =nOH- nên phản ứng vừa đủ

pH của dd Y=7

theo mình giải là như vậy

Explanation:

Explanation:

basically, you'll just have to convert the given grams into moles, convert that into moles of Br, and then convert it again into grams of Br

The amount of gram of [tex]Br_{2}[/tex] will be  65.1 grams in equation [tex]2AlCl_{3} + 3Br_{2}[/tex]→ [tex]2AlBr_{3} + 3Cl_{2}[/tex].

The definition of a gram was given as the mass of one cubic centimeter of pure water at 4 degrees Celsius.

Calculation of amount of  [tex]Br_{2}[/tex]

The given equation is [tex]2AlCl_{3} + 3Br_{2}[/tex]→ [tex]2AlBr_{3} + 3Cl_{2}[/tex].

The mass of  [tex]Br_{2}[/tex]  = Count of bromine molecule × molar mass

The mass of  [tex]Br_{2}[/tex]   = 0.4072 × 159.8

The mass of  [tex]Br_{2}[/tex]   = 65.08 mol.

The amount of gram of  [tex]Br_{2}[/tex]  will be  65.1 grams in equation  [tex]2AlCl_{3} + 3Br_{2}[/tex]→ [tex]2AlBr_{3} + 3Cl_{2}[/tex].

Therefore, the answer will be option (a).

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Answer:

the answer is the number of gas molecules changes.

Answer:

C is Correct

Explanation:

Protons and Neutrons make up the Nucleus while Electrons surround the nucleus in circular orbits with continuous rotation.

Answer:

A. They are in the nucleus and never leave.

Explanation:

Protons as well as neutrons are located in the nucleus of the atom.

hope this helps!

Answer:A force is a push or pull upon an object resulting from the object's interaction with another object.

A force acting on an object causes the object to change its shape or size, to start moving, to stop moving, to accelerate or decelerate

Answer:

the answer to this problem is a

Answer:

3 exothermic reaction. only that much

Hi,

These are the answers.

• Question 2. C , Substance dissolves

• Question 3. D , Exothermic reaction

• Question 4. C , Endothermic reaction takes place

• Question 5. A , the products formed has more energy than reactants

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Answer:

magnesium chloride: MgCl2

zinc sulphide: ZnS

sodium sulphate: Na2SO4

calcium bicarbonate: Ca(HCO3)2

Option B, Metals have good conductivity.

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Answer:

D)driying of limonite these is the answer

Answer:

1.false

2.neutron

3.neutron

Answer:

1. false

2. zero

3. isotopes

hope it helps

Answer: A is correct. I don't see the "element shown below," but it isn't needed to answer this question.

Explanation: By definition, the atomic mass is based on the sum of protons (1 AMU each) and neutrons (1 AMU each). Electrons are assigned a value of 0 AMU.

Answer:

See explanation below for answers

Explanation:

0.00305

0.00310

0.00300

0.00305

0.00305

When there is a decimal point, you must skip the zeros until you reach a number. Once you reach that number, you move 2 more places to the right of that number in order to have 3 significant figures. Hope this helps!

In an experiment, we can define 3 types of variables.

Independent variables: Are these ones that the scientist can control and modify, in this case, would be the kind of rubber for the tires.

Dependent variables: Are the variables that react to the changes in the independent variables. In this case, would be "how much lasts each type of rubber".

Controlled variables: Are all of these variables that also have an impact on the dependent variable, so we need to control them (fix them) so they do not affect the study of the independent variable.

So, for this particular experiment, to find controlled variables we need to think on what things do affect the durability of tires.

Some examples can be:

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Answer: 37 protons, 48 neutrons, and 36 electrons.

Explanation: I assume "Revision" is Rubidium. It is atomic number 37, so it has 37 protons. It's atomic mass is 85, so it has an average of (85-37) = 48 neutrons. It has a charge of +1, so one electron of the original 37 has left.

Answer:

Water, H2O, is a pure substance, a compound made of hydrogen and oxygen. Although water is the most abundant substance on earth, it is rarely found naturally in its pure form. Most of the time, pure water has to be created. Pure water is called distilled water or deionized water.

Answer:

C. the amount of drug x given to mice

Answer:  1.8x10^-4 M H+

Explanation:  The number of moles of NaOH added to the 100 ml soultion will be equal to the number of moles of H+ present in that solution.  

Moles NaOH in 7.2 ml of 2.5x10^-3 M NaOH

(2.5x10^-3 M NaOH) is the same as 2.5x10^-3 moles NaOH/liter

(2.5x10^-3 moles NaOH/liter)*(7.2 ml)*(1 liter/1000ml) = 1.8x10^-4 moles NaOH used to titrate 100 ml of the acid.  That means there was 1.8x10^-4 moles of H^+ in 100 ml.  

Concentration of H^+ = (1.8x10^-4 moles H)/0.100 l) = 1.8x10^-4 M H+

(pH of 3.74)

answer/

1 grams Calcium Phosphate to mol = 0.00322 mol

no. of moles= 0.00322×25

no. of moles = 0.0805

Answer:

hello ~~

look nucleus is mixture of neutrons and protons.. right?

and we know neutrons have no charge and protons are positively charged so overall charge of nucleus is positive

Answer:

D. all of the elements of Group 18 in orange boxes

Answer:

The bond formed between XY is "Ionic bond"

Explanation:

The bond is ionic bond because the compound XY is formed due to the gaining and loosing of electrons

Properties of Ionic compounds:

They form crystals

They are good insulators

They have high melting and boiling points

.

.

.

Hope it helps

Answer:

solutions is a homogenous mixture while colloids and suspensions are heterogeneous mixtures made up of 3 or more substances

Explanation:

homogeneous- made up of one thing

heterogeneous- made up of 2 or more things

Answer:

It would take sound 104.998 seconds to travel across lake tahoe.

Explanation:

First let's convert the miles to meters, so, 21.6 miles = 34754.4 meters

Now, we will divide this number in meters by 331. So, 34754.4 / 331 = 104.998

And what will the unit be? Seconds will be the unit for time here so 104.998 seconds.

The parts of the text on the page that use examples of how the flow of matter through a system is energy driven and has the capacity to do work are;

1) The flow of water down rivers passing through hydro power dams to perform the following works;

2) The flow of electrons that corresponds to the flow of electricity (in the reverse direction) to perform the following works;

3) The lifting of the hammer by the cam which gains gravitational potential energy that is converted to kinetic energy as the hammer drops

The hammer is repeatedly lifted and dropped by the cam to do the following work

4) The chemical potential energy stored in bonds by virtue of the relative atomic distances which produces kinetic energy from the chemical potential energy

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