what is an atomic mass unit?​

Answer:

719.83°C

Explanation:

The heat that the sample of Zinc gives is equal to the heat that water is absorbing. That is:

C(Zn) * m(Zn) * ΔT(Zn) = C(H2O) * m(H2O) * ΔT(H2O)

Where:

C is specific heat (Zn: 0.390J/g°C; H2O: 4.184J/g°C)

m is mass (Zn: 2.50g; H2O: 65.0g)

ΔT (Zn: ?; H2O: (22.5°C - 20.0°C = 2.50°C)

Replacing:

0.390J/g°C * 2.50g * ΔT(Zn) = 4.184J/g°C * 65.0g * 2.50

ΔT(Zn) = 697.33°C

As final temperature of Zn is 22.50°C, initial temperature is:

Initial temperature: 697.33°C + 22.50°C

719.83°C

Answer:

Ca + AgNO3 ---> Ca(NO3)2 + Ag

Calcium + silver nitrate ---> Calcium nitrate + silver

also ...reaction type is Single displacement reaction .

hope this answer's your question.

Answer:

A pure substance has a definite chemical composition

A pure substance has a definite chemical composition in all states. Pure substance can be composed of multiple elements but the composition does not alter in any case.

Pure substances are formed either a single component or a combination of more components with a definite composition forming a single phase. Unlike mixtures a pure substance cannot be separated into its components physically.

For example pure water is a pure substance. Water is formed from hydrogen and oxygen atoms in a definite proportion forming a molecular compound that does not alter anyway.

However, salt solution, mixture of two gases etc. are not pure substance. They haven't a definite composition and can be separated by some physical methods. Hence, option c is correct.

Find more on pure substances:

https://brainly.com/question/24462192

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Answer:

480.6 g

Explanation:

Given data:

Number of molecules of methanol = 9.01 ×10²⁴

Mass in gram = ?

Solution:

The given problem will solve by using Avogadro number.

It is the number of atoms , ions and molecules in one gram atom of element, one gram molecules of compound and one gram ions of a substance.

The number 6.022 × 10²³ is called Avogadro number.

1 mole = 6.022 × 10²³ molecules

9.01 ×10²⁴molecules ×1 mol /6.022 × 10²³ molecules

1.5 ×10¹ mol

15 mol

Mass in gram:

Mass = number of moles × molar mass

Mass = 15 mol × 32.04 g/mol

Mass = 480.6 g

Answer:

B or C

Explanation:

I don't really know sorry.

Answer:

D

Explanation:

I think D I also took the test.

One of the most polluting being city sewage and industrial waste discharge. Indirect sources of water pollution include contaminants that enter the water supply from soils or groundwater systems and from the atmosphere via rain.

Answer:

gas gets dumped is one and the other is dumping trash into water

Explanation:

Answer:

If it took the motorcycle 2 hours to cover 20km, then the average speed is 10km per hour.

Explanation:

Speed is equal to distance over time. So 20km divided by 2 hours is 10 km per hour.

Please mark brainliest!!! Thanks.

Answer:

96.56063 km/h

Explanation:

Aluminum has the larger atomic radius.

silicone is larger than carbon.

Aluminum is larger than silicon

I think silicon is the answer

Answer:

electric field or magnetic field both are same

Explanation:

in an electromagnet the movement of electrons in a wire creates the magnetic field.an electromagnet and the permanent magnet both the magnet have the magnetic fields that can attract the same kinds of materials.

Answer: Answer to your question is B. I did a science

Explanation: Test was to see which would dissolve fastest...

Answer:

B

Explanation:

b/c air is not seen by eye

Answer:

Answer:

Divide 837.4 g by 18.015 g/mol to get moles of H2O

Multiply moles of H2O by 6.022 x 10^23 molecules/mol to get molecules (of H2O in 837.4 g)

Round off your final answer to 4 sig figs.

Thank you and please rate me as brainliest as it will help me to level up

Answer:

NaCl

Explanation:

The only chemical species that shows an ionic compound is NaCl.

NaCl is an ionic compound that conducts electricity in molten state due to presence of free mobile electrons in the structure when molten.

Answer:

 it is A i took the test could i have the crown please

Explanation:

Answer:

0.75M Fe²⁺

Explanation:

First, we need to balance the redox reaction in acidic medium. Then, we can obtain moles of KMnO4 and with the reaction moles and molarity of the Fe²⁺ solution:

Redox Balance:

Fe²⁺ → Fe³⁺ + 1e⁻

5e⁻ + 8H⁺ + MnO₄⁻ → Mn²⁺ + 4H₂O

___________________________

5Fe²⁺ + 5e⁻ + 8H⁺ + MnO₄⁻ → 5Fe³⁺ + 5e⁻ + Mn²⁺ + 4H₂O

Moles of KMnO₄:

70.0mL = 0.0700L * (0.150mol / L) = 0.0105 moles KMnO₄

Moles and molarity Fe²⁺:

0.0105 moles KMnO₄ * (5 moles Fe²⁺ / 1mol KMnO₄) = 0.0525 moles Fe²⁺

In 70.0mL = 0.0700L:

0.0525 moles Fe²⁺ / 0.0700L =

Answer:

6. Color Change.

Production of an odor.

Change of Temperature.

Explanation:

That is the only one I know :)

Answer:

6. 3 things could potentially be, a change in mass, a change in color, or a change in weight. obviously there are more, but these are 3.

I'm sorry I couldn't answer more of these question of yours, I don;t know too much about aluminium :/

May I have brainliest please? :)

To Find :

How many molecules are in 23 moles of oxygen (O₂).

Solution :

We know, 1 mole of any atom/molecule contains 6.022 × 10²³ numbers of atoms/molecules.

So, number of molecules in 23 moles of O₂ are :

[tex]n= 23\times 6.022\times 10^{23}\\\\n =138.506\times 10^{23}\\\\n = 1.385 \times 10^{25}\ molecules[/tex]

Hence, this is the required solution.

Answer:

the rate is faster, and the time of reaction is 28 seconds

Explanation:

i did the test

Answer:

The rate is faster, 28 seconds

Explanation:

Answer:

 r =  [tex]\sqrt{\frac{v}{\pi h} }[/tex]

27.2cm

Explanation:

Given parameters:

Height of tank  = 6461.76cm

Volume of water  = 15000000cm³

Volume of cylinder  = [tex]\pi[/tex] r² h

i. Express radius in terms of volume;

  we are to make radius the subject of the expression;

              v = [tex]\pi[/tex] r² h  

     divide both sides by πh

         [tex]\frac{v}{\pi h}[/tex]   = [tex]\frac{\pi r^{2}h }{\pi h }[/tex]  

              r²   =  [tex]\frac{v}{\pi h}[/tex]

              r =  [tex]\sqrt{\frac{v}{\pi h} }[/tex]

ii.

Radius of the water tank;

             r  = [tex]\sqrt{\frac{15000000}{\pi x 6461.76} }[/tex]   = 27.2cm

Answer: A. Thermometer

Explanation:

A thermometer is used to measure temperature , while the others measure different things.

Answer:

protons = 9

neutrons = 10

electrons = 9 because it is neutral atom

Explanation:

atomic number= protons = 9

atomic mass= protons + neutrons

19= 9 + n

n= 10

Answer:

The correct answer is - Orange light reflected from the t-shirt enters human eyes.

Explanation:

Human eyes and brain are altogether able to detect the color of the object by translating the light which is reflected by the object and transmitted by the light receptors in the eyes ad brain translate light to color.

The objects are able to absorb some colors and reflect others on the basis of their wavelength, The reflected colors are detected by our eyes and brain and objects appear to be a particular color. like here, the orange color is reflected by the t-shirt and enters in human eyes.

Answer:

its c

Explanation:

1. C

2. D (I’m not entirely sure)

3.energy can neither be created nor destroyed, only change forms.

4. C

5. A

6. C

I’ve researched and tried to answer these questions correctly.

Answer:

1.c

2.a

3.created or destroyed

4.c

5.a

6.c

Explanation:

thanks me later

Answer:

the words to identify them is them in kaps right

Explanation:

Answer:

B. The nickle Metal

Explanation:

A P E X

Answer:

I believe the correct answer is D.

Explanation:

You are breathing in dinitrogen and dioxygen. You exhale dinitrogen and carbon dioxide. And the atmosphere contains traces of other gases. You drink water. You have a wash with water, and soap. You eat carbohydrates and proteins. You ride to work on a vehicle powered by hydrocarbons, which spits out carbon dioxide exhaust fumes, and also some nitrogen oxides. And so your exposure to chemicals is pervasive, and unavoidable.

Answer:

d

Explanation:

Answer:

Radiation you're welcome <3