1 poin
9. In an experiment, the one variable that is changed on purpose by the
scientist is called the
controlled variable
experimental variable
independent variable
dependent variable

Answers

Answer 1

Answer:

It's called Independent variable

Explanation:

....


Related Questions

Which of the following are chemical or nuclear reactions?

1. chemical plant explosion
2. Tsar Bomba
3. meteor strike
4. Tunguska Event
5. Super Volcano eruption
6. fusion powering the sun

Answers

Answer:5) super Volcano eruption

Explanation:

Answer:

#1, #2, #4, and #6 are the answers.

Explanation:

#2, #4, and #6 have something to do with radioactivity which is mostly categorized in nuclear reactions, #3 and #5 are partly categorized in thermal reactions while a chemical plant explosion is almost categorized as a chemical bomb; Chemical explosions may be either decomposition or combination reactions. Decomposition reactions occur in materials such as trinitrotoluene (TNT) and nitroglycerine. Combination reactions require that two or more components react together exothermically to produce hot gases. Some examples are ammonium nitrate and fuel oil (ANFO), and gunpowder (potassium nitrate, carbon, and sulfur). In conclusion, #1, #2, #4 and #6 are the answers.

The composition of a compound is 6.27 g calcium and 1.46 g nitrogen.
Calculate the empirical formula.

Answers

Answer:

Ca₃N₂

Explanation:

The empirical formula is the simplest whole-number ratio between moles of each element present in a molecule.

Thus, we need to convert mass of each atom to moles and find the ratio between these as follows:

Moles N:

1.46g * (1mol / 14.0067g) = 0.104moles

Moles Ca:

6.27g * (1mol / 40.078g) = 0.156moles

The ratio between Moles N and moles of Ca is:

0.156moles / 0.104 moles = 1.5

That means there are 1.5 moles of Ca per mole of N. As empirical formula must be given in whole numbers:

There are 3 moles of Ca per 2 moles of N.

Empirical formula is:

Ca₃N₂

Any 1 help with Chemistry here??

Answers

Nope sorry bro:((((((

can someone solve c and d? ​

Answers

Answer:

Na + + e - → Na.

Pb 2+ + 2e - → Pb.

2H + + 2e - → H 2

Explanation:

Which chemical equation below is balanced to correctly represent the Law of Conservation of Mass?

Answers

Answer:

The 3rd equation.

Cl2 + 2NaBr —> 2NaCl + Br2

Explanation:

The law of conservation of matter (mass) states that matter can neither be created nor destroyed during a chemical reaction but can be transferred from one form to another. This implies that unbalanced chemical equation shows that matter (mass) has been created or destroyed.

Now, we shall determine which equation is balanced as follow:

1. 2Cl2 + NaBr —> 2NaCl + Br2

Reactant >>>>>>>> Product

4 Cl >>>>>>>>>>>> 2 Cl

1 Na >>>>>>>>>>>> 2 Na

1 Br >>>>>>>>>>>> 2 Br

Thus, the equation is not balanced.

2. Cl2 + NaBr —> NaCl + Br2

Reactant >>>>>>>> Product

2 Cl >>>>>>>>>>>> 1 Cl

1 Na >>>>>>>>>>>> 1 Na

1 Br >>>>>>>>>>>> 2 Br

Thus, the equation is not balanced.

3. Cl2 + 2NaBr —> 2NaCl + Br2

Reactant >>>>>>>> Product

2 Cl >>>>>>>>>>>> 2 Cl

2 Na >>>>>>>>>>> 2 Na

2 Br >>>>>>>>>>>> 2 Br

Thus, the equation is balanced.

From the illustration made above only the 3rd equation is balanced. And this is in line with the law of the Conservation of matter (mass) as matter (mass) was not created nor destroyed during the chemical reaction but was transferred to other forms.

In the redox reaction AgNO3 + Na → NaNO3 + Ag, which element has been
oxidized?

Answers

Answer:

sodium I think .............

How many molecules are in 32 grams of NH3?

Answers

Answer:

1.87897962011728

Explanation:

What is the final temperature when 625 grams of water at 75.0° C loses 7.96 x 104 J?
The specific heat of water is 4.18 J/gCº.

Answers

Answer: A copper cylinder has a mass of 76.8 g and a specific heat of 0.092 cal/g·C. It ... J ql = mwcwΔTw. ΔTw = ql/(m x c). ΔTw = 7.96 x 10. 4. J/(625 g x 4.18 J/g·K) = 30.5 ...

Explanation:

Which of these is an example of physical change

A) iron melting
B) steel rusting
C) paper burning
D) wood decaying ​

Answers

Answer:

it is A mark me big brain pls

Explanation:

I would say d sorry if it is wrong

What is chemical potential energy?
A. Energy stored by atoms
B. Energy stored in height differences
C. Energy from gravity
D. Energy of motion

Answers

Answer:

A

Explanation:

please pick me for brainliest

Answer:

D

Explanation:

All about the motion.

BEBE
Use the activity series below to predict whether the following reactions will take place.
803
F2 > Cl2 > Br2 > 12
Cl2 + 2Rbl - 2RbCI+ 12
12 + NiBr2 - Nil2 + Brz
yes
yes
no
0
no

Answers

Reaction 1 : yes

Reaction 2 : no

Further explanation

The metal activity series is expressed in voltaic series  

Li-K-Ba-Ca-Na-Mg-Al-Mn- (H2O) -Zn-Cr-Fe-Cd-Co-Ni-Sn-Pb- (H) -Cu-Hg-Ag-Pt-Au  

The more to the left, the metal is more reactive (easily release electrons) and the stronger reducing agent  

The more to the right, the metal is less reactive (harder to release electrons) and the stronger oxidizing agent

So that the metal located on the left can push the metal on the right in the redox reaction  

From activity series of Halogen :

F₂>Cl₂>Br₂>I₂

F₂ is the strongest oxidizing agent

1. Reaction

Cl₂ + 2Rbl - 2RbCI+ I₂

Cl₂>I₂⇒reaction can occur⇒yes, reactions will take place.

2. Reaction

I₂ + NiBr₂ - NI₂ + Br₂

Br₂>I₂⇒Reaction can't occur⇒no, reaction will not take place

how does carbon dioxide get into the atmosphere?

Answers

Answer:

By condensation.

Explanation:

Have a nice day dear

when organisms respire or decompose (decay), carbonate rocks are weathered, forest fires occur, and volcanoes erupt

which of the following is not the same as 0.032 liters?
a)32 mL
b)0.00032 hL
c)320 cL

Answers

C) why because it’s says 320 cL wich means that.....

The large holes that can form in Limestone eventually lead to the formation of caves and caverns.

True or False?

Answers

Answer:
True
Explanation:
Because it would be false That Caves and caverns are common in dry regions where these is a layer of limestone near the surface.

HELPPPP!!! I NEED IT VERY MUCHHHH

Answers

Answer:

mabye C at least if its not right sorry .

state the volume of SO2 and O2 at RTP that would produce 180cm3 of SO3

Answers

Answer:

(180 cm^3 SO3) x (2 mol SO2 / 2 mol SO3) = 180 cm^3 SO2

(180 cm^3 SO3) x (1 mol O2 / 2 mol SO3) = 90 cm^3 O2

What type of relationship exists between
dissociation constant and pk values

A Linear
B Directly Proportional
C Direct
D Inverse

Answers

Answer: D inverse . The product of Ka and Kb equals the auto-dissociation constant for water.

Explanation: i hoped that helped and Plz give as a brainliest !!

I think the answer would be D Inverse, but I’m not 100%

IMMA WAIT FOR MY BABY EVEN IF IT TAKES ALL NIGHT !!!!!!

Answers

Answer:

um okay lol

Explanation:

Answer:

Oh ok

Explanation:

Also can u pls mark me brainliest im new pls

Which of the following statements is true?

A. Cations are always larger than the atoms from which they form.
B. Cations are always the same size as the atoms from which they form.
C. Anions are always larger than the atoms from which they form.
D. Anions are always smaller than the atoms from which they form.

Answers

Answer:

B. Cations are always the same size as the atoms from which they form.

Explanation:

That's i read in the book

"Anions are larger in size than the atoms from which they form" is a true statement. Therefore, option (C) is correct.

What are anions and cations?

A cation contains more protons than electrons in it, which give it a net positive charge. A cation can be formed by losing one or more electrons must be lost by atoms.

The charge on the ion will be equal to the number of electrons lost as indicated after the chemical symbol. For example, silver (Ag) has lost one electron to become Ag⁺. The size of the cation is always smaller than the atom from which it formed.

An anion contains more electrons than protons which gives it a net negative charge. An anion can be formed by gaining one or more electrons or typically pulled away from other atoms.

The charge of the anion will be equal to the number of electrons gained, which is indicated after the chemical symbol.  For example, chlorine (Cl) accepts one electron to become Cl⁻.

The size of an anion is greater than the atoms from which it formed as the number of electrons in the ion increases and effective nuclear charge decreases.

Learn more about anions and cations, here:

https://brainly.com/question/20435320

#SPJ2

what is the main material that make up the tusk of an elephant​

Answers

Answer:

Ivory

Explanation:

The outside of the tusk is made of ivory, but 2/3 of the tusk is their head, made of tissue. But I think the answers Ivory. Thats the reason why poachers go for the tusks. Because humans like ivory :/

The main material that makes up the tusk of an elephant is Ivory

Express in scientific notation. Choose the answer with the proper number of significant figures.
9x109
4.5 x 10

Answers

Answer:

4.5 times 10 = 45

Explanation:

"Non-zero digits are always significant. Any zeros between two significant digits are significant. A final zero or trailing zeros in the decimal portion ONLY are significant."

A science teacher placed a magnesium wire in flame.the wire turned white where the flame touched it. which statement best explains the chemical change

A. a new substance formed

D. the magnesium wire changed shape

the subject is science

Answers

Answer:

A

Explanation:

The correct answer would be that a new substance is formed.

When magnesium wire is burnt in the presence of oxygen, the wire reacts with oxygen and a new substance known as magnesium oxide is formed. The new substance is usually white in color and the equation of the reaction is as below:

[tex]2 Mg (s) + O_2 (g) --> 2 MgO (s)[/tex] (white)

Hence, the correct option is A.

Answer:

Explanation:A new substance formed. Promise.

A chef fills a 60-ml container with 45.3 g of cooking oil. What is the density of the oil?

Answers

Answer:

0.76 g/mL

Explanation:

The density of a substance can be found by using the formula

[tex]density = \frac{mass}{volume} \\ [/tex]

From the question we have

[tex]density = \frac{45.3}{60} \\ = 0.755[/tex]

We have the final answer as

0.76 g/mL

Hope this helps you

Which gas contains the same number of molecules as 9g of water?
A) 2g of hydrogen
B) 14g of nitrogen
C) 32g of oxygen
D) 44g of carbon dioxide​

Answers

Answer:

B) 14g of nitrogen

Explanation:

To calculate number of molecules in 9g of water, we first convert mass to mole by using mole = mass/molar mass i.e.

mole = 9g/18g/mol of water

mole = 0.5mol

Next, we multiply by 6.022 × 10^23 molecules to get 3.011 × 10^23 molecules in 9g of water (H2O).

- For hydrogen gas: Molar Mass = 2g/mol, mass = 2g

mole = 2/2 = 1

No. of molecules = 1 × 6.022 × 10^23 = 6.022 × 10^23 molecules.

- For Nitrogen gas: Molar Mass = 28g/mol, mass = 14g

mole = 14/28 = 0.5mol

No. of molecules = 0.5 × 6.022 × 10^23 = 3.011 × 10^23 molecules.

- For Oxygen gas: Molar Mass = 32g/mol, mass = 32g

mole = 32/32 = 1mol

No. of molecules = 1 × 6.022 × 10^23 = 6.022 × 10^23 molecules.

- For carbondioxide gas: Molar Mass = 44g/mol, mass = 44g

mole = 44/44 = 1mol

No. of molecules = 1 × 6.022 × 10^23 = 6.022 × 10^23 molecules.

Based on he results of each calculation, NITROGEN contains the same number of molecules as 9g of water

SIMPLE ANSWERS ONLY I ALREADY GOOGLED AND DIDN'T FIND ANYTHING PLEASE ANSWER IN YOUR OWN WORDS.

How is atomic mass calculated for elements on the periodic table.

Answers

Explanation:

The atomic mass of elements on the periodic table are derived from the proportion of the geonormal abundance of the different isotopes of an element.

Using a mass spectrometer, the proportion/percentage/fraction by which each of the isotopes of an element occurs in nature is determined. This proportion is the geonormal abundance. From this the atomic mass of the element can be derived. Simply multiply the mass by the abundance and sum the values for the same isotopes together.

Match the definitions on the left with the terms on the right.

Answers

Answer:what defino? I don’t see nun

Explanation:

Answer:

answer in picture

Explanation:

I don’t really have a question... and my teacher says I need to give one related to this reading above :/

Can somebody plz give one that makes sense (WILL MARK BRAINLIEST)

Answers

Answer:

Just say I wonder why teachers give homework :/

Explanation:

The diagram shows changes of state between solid, liquid, and gas. The atoms of a substance lose energy during a change of state. Before the change, the atoms are close together but are able to slide past one another.Which arrow represents the change of state described above?

M
N
P
Q

Answers

P - solid to liquid.

Answer:

D. P

Hope it works!

Explanation:

How many valence electrons would be shown in the electron dot diagram of a helium atom?

Answers

Answer:2

Explanation:

The number of valence electrons for a helium atom is 2. This can be confirmed by looking at the electronic configuration.

Helium atom:

Helium is placed in the noble gas series as it has certain properties of it. The atomic number of helium is 2. Thus, it has two electrons in its outermost shell but it has completely filled orbital.

Electronic configuration of He = 1s2

Thus, for drawing the electron dot structure, there are two valence electrons.

Find more information about Helium atom here:

brainly.com/question/26226232

2. If 300.0 mL of a 2.5 M solution of nitric acid is added to 500.0 mL of water, what is the molarity of the
dilute solution?

Answers

Answer:To calculate the Molarity of a 70 wt. % Nitric Acid the number of moles of HNO 3 present in 1 liter of acid needs to be calculated. Knowing the density of the acid to be 1.413 g/mL, we can calculate the weight of 1 L of 70% HNO 3 to be 1413

Explanation:

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En tu trabajo de ciencias te toco realizar un experimento de cultiv de hongos en una pieza de pan de harina de trigo y una tortilla de maiz. La secuencia de revisin para la toma de datos ser, en el primer caso, cada 15 dias; y en el otro, cada 20 por tres meses. A los cuantos das te tocara revisar ambos cultivos? 6. Kennedy says that America shouldA focus solely on medical space research.B divide the work among other nations. take the lead in space exploration.D partner with other superpowers.Please send help Handwashing can be done in any sink found in the kitchen. 15 pnts for both answers The factory floor supervisor started the generator _____ the power had gone out. Which of these sets of measurements represents the lengths of the sides of a right triangle? a. (10, 24, 26) b. (5, 12, 24) c. (12, 18, 30) d. (1, 2, 9) Read the excerpt from "Amigo Brothers. The fight had created great interest in the neighborhood. Antonio and Felix were well liked and respected. Each had his own loyal following. Betting fever was high and ranged from a bottle of Coke to cold, hard cash on the line. This passage is part of the storys exposition. climax. falling action. resolution. When a person prevails they..Question 19 options:shaking in a threatening waygain the desired effectfearlessmorally right Use a formal definition to define you Family how did neighboring empires respond to the israelites for an individual with an open fracture of the leg, what would be an appropriate action have the person lie down start cpr keep the person walking apply heat What purpose does bride price or bride wealth serve?A) It gives the groom rights to the bride's children.D) It establishes the market value of women in the society.C) It proves that the groom will be able to provide for his bride financially.D) It acts as a loan to the bride's family that can be invested for the benefit of future offspring. Last year, Renata earned $540 delivering newspapers. This year, Renata made 250% of what she made last year?A tape diagram. 0 dollars is 0 percent. Question mark dollars is 250 percent.Which steps should you take to find out how much money Renata made delivering newspapers this year? Check all that apply.Convert 250% to a decimal to get 0.25.Convert 250% to a decimal to get 2.50.Multiply 0.25 by 540 to get $135.Multiply 2.50 by 540 to get $1,350.Check your answer by using 100% + 100% + 50% to get 540 + 540 + 270. compare and contrast night time and day time The college student who is looking for a data plan for her cell phone found a third option,which also offers a 2 gigabyte monthly allowance for data.The monthly cost of this option can be represented by function C defined by:C(x) = 30x + 5, where x is the gigabytes of data used over the monthly allowance.1. Find C(0.7) and explain what it means in this situation, A quadratic function is increasing to the left of x = 2 and decreasing to the right of x =2. Will the vertex be the highest or lowest point on thegraph of the parabola? Explain. A republic form of government BEST described as A. One in which all citizens meet regularly to discuss issuesB. One in which the people elect representatives to rule for the C. One in which all power is in the hands of a single person D. One in which the people rule themselves what Is thee error and the solution Match the given latent print detection technique to the surfaces on which they can be used.using ninhydrinfuming with superglue fumingfuming with iodinedusting with carbon powderexposing to silver nitrateusing magna brushPorous SurfaceNon-porous Surface Which of these is a chemical property used to identify minerals?O A. ReactivityO B. ColorO C. LusterO D. Hardness