Chemistry Middle School

What is the answer ?

Answers

Answer 1

Answer: c

Explanation: an xray wave does have a higher frequency than an infrared wave.

Answer 2

Answer:

Explanation:c

Related Questions

Katie throws a 3 kilogram ball fast at a speed of 15 meters what is the momentum of the ball katie threw

Answers

Answer:

Hey!

Your answer is 45kg.m/s

Explanation:

Using the formula P=M x V

(p=momentum...M=mass...V=velocity)

We do M x V

15 x 3

Which gives us an answer of 45kg.m/s!

HOPE THIS HELPS!!

how does the sun light affect earths climate

Answers

Answer:

The Sun powers life on Earth; it helps keep the planet warm enough for us to survive. It also influences Earth’s climate: We know subtle changes in Earth’s orbit around the Sun are responsible for the comings and goings of the past ice ages. But the warming we’ve seen over the last few decades is too rapid to be linked to changes in Earth’s orbit, and too large to be caused by solar activity

Explanation:

Which formula represents an isomer of CH3−CH2−COOH?

CH3−CO−O−CH3

CH3−CO−CO−CH3

CH3−C−OH−CH3

CH3−CH2−CO2−CH3

Answers

Answer:

CH3−CO−O−CH3

Explanation:

i just took the test

How many total atoms from Carbon are present on the reactant side?
20 points
2CH2+202
O2+HC4
5
2
1
3

Answers

Answer:

2 carbon atoms/molecules are present on the reactant side.

hope it helps!

NEED HELPPP PLSSSSSSSSSS

Answers

I would pick the first option in the third option

Which of these Electromagnetic waves has the most kinetic energy and can be
dangerous?
O radio waves
O gamma rays
O ultraviolet waves
O visible light

Answers

Answer:

Gamma Rays.

Explanation:

Gamma-ray photons have the highest energy in the EMR spectrum and their waves have the shortest wavelength.

how many Atoms of chlorine Cl are there in 3.45 mol Cl?

Answers

Answer:

2.078x10^24

Explanation:

No. of atoms of chlorine = 3.45 x 6.022x 10 ^23 x 1

= 2.078x10^24

( to find no. of atoms of, heres the formula i was taught No. of atoms = no. of moles x Avogadros constant x no. of atoms in the formula of compound)

Which situation describes why a rock sinks in water?
A. Air pressure is greater than the buoyant force.
B. The force of gravity is greater than the buoyant force.
c. The buoyant force is greater than the force of gravity.
D. The rock is less dense than water.

Answers

Answer:

Explanation:

PLEASE HELP :"( DUE NOW!!

What is the equation for the equilibrium constant for this equation?

CO+3H2⇌CH4+H2O

[H2O][H2]/[CH4][CO]

[CO][H2]3/[CH4][H2O]

[CH4][H2O]/[CO][H2]3

[CH]4[H2O]/[H2]3

Answers

Answer:

The correct answer is

[CH4][H2O]/[CO][H2]3

Option 3 is correct

Explanation:

Step 1: Data given

For the equation aA + bB ⇆ cC + dD

The equilibrium constant is [C]^c * [D]^d / [A]^a*[B]^b

Step 2: Calculate the equilibrium constant Kc

CO+3H2⇌CH4+H2O

Kc = [H2O][CH4] / [CO][H2]³

The correct answer is

[CH4][H2O]/[CO][H2]3

Option 3 is correct

Relate dark matter to the development of the universe after the Big Bang. In 3-5 sentences, speculate on how the development of the universe would have been different if there had been no dark matter. In your answer, use the term structures.

Please answer this and ill mark you as brainliest

Answers

Answer:

Dark matter also called baronic matter is the matter that makes up 27% of the universe.

In 1933 it was determined as that mass that cannot be seen, that is, the non-visible mass of outer space.

Dark matter also plays a central role in the formation of structures and the evolution of galaxies and has measurable effects on the anisotropy of cosmic microwave background radiation. The composition of this matter is unknown today.

The dark matter component has considerably more mass than the "visible" component of the Universe.

Explanation:

There are certain researchers who say that the appearance of dark matter was before the appearance of the big bang.

A relevant fact of this matter is that dark matter exerts gravity, and that gravity affects the movements of objects.

Despite the fact that nothing is known about its origin, astronomers have amply demonstrated that dark matter plays a determining role in the formation of galaxies and galactic clusters, which could not maintain their cohesion without its existence, but many doubt that it is the remainder / remnant or product of a big bang.

What is the mole fraction of Ba(OH)2 in an aqueous solution that contains 22.8% Ba(OH)2 by mass?

Answers

Answer:

0.03

Explanation:

22.8 g Ba(OH)2 (1 mol Ba (OH)2/ 171.34 g) = 0.133 mol Ba (OH)2

77.2 g H2O (1 mol H2O/18 g) = 4.29 mol H2O

X= molar fraction= mol Ba(OH)2/ mol total

X= 0.133/ (0.133+4.29) = 0.03

0.03 is the mole fraction of [tex]Ba(OH)_2[/tex] in an aqueous solution that contains 22.8% [tex]Ba(OH)_2[/tex] by mass.

What is a mole fraction?

The ratio of the number of moles of one component of a solution or other mixture to the total number of moles representing all of the components.

Moles of [tex]Ba(OH)_2[/tex]

Moles = [tex]\frac{mass}{molar \;mass}[/tex]

Moles = [tex]\frac{22.8 g Ba(OH)_2}{171.34 g}[/tex]

= 0.133 mol [tex]Ba (OH)_2[/tex]

Moles of [tex]H_2O[/tex]

[tex]Moles = \frac{mass}{molar \;mass}[/tex]

[tex]Moles = \frac{77.2 g H_2O}{18 g}[/tex]

= 4.29 mol [tex]H_2O[/tex]

The mole fraction of [tex]Ba(OH)_2[/tex]

[tex]\frac{mol Ba(OH)_2}{total \;mol}[/tex]

= 0.03

0.03 is the mole fraction of [tex]Ba(OH)_2[/tex] in an aqueous solution that contains 22.8% [tex]Ba(OH)_2[/tex] by mass.

Learn more about the mole fraction here:

https://brainly.com/question/8076655

#SPJ2

Fossil fuels, like coal, oil, and natural gas, are huge, carbon-rich deposits that essentially trapped carbon for millions of years (until humans started burning them for energy).

True or False

Answers

Answer:

True!

Explanation:

Fossil fuels are carbon based compounds present deep in the earth left millions of years ago.

hope it helps!

How is a lithium atom (Li) different from a lithium ion (Li+)?

Li has fewer electrons than Li+
Li has more electrons than Li+
Li has fewer protons than Li+
Li has more protons than Li+

Answers

Answer:

Li has fewer protons than Li+

Li has fewer electrons than Li+

How could you determine if a car door is made of a material, such as plastic?

Answers

Answer:Most cars have the visible outer panel, and supporting structure, made from steel. Some use aluminium, at least one series-produced model had magnesium doors, and there are also doors where the visible parts are plastic or fiberglass, with some sort of metal inside for strength.

Explanation:

Answer:

Most cars have the visible outer panel, and supporting structure, made from steel. Some use aluminium, at least one series-produced model had magnesium doors, and there are also doors where the visible parts are plastic or fiberglass, with some sort of metal inside for strength.

A typical cell phone uses wavelength of 0.36meters. How much energy does this wave have?

Answers

Answer:

55×10^-26 J

Explanation:

We can calculate the energy of the wave from

E= hc/λ

Where

h= Planks constant = 6.6×10^-34 Is

c= speed of light = 3×10^8 ms-1

λ= wavelength of the wave = 0.36 metres

Recall that cell phone use radio waves which belong to the electromagnetic spectrum hence it must possess the speed of light.

E= 6.6×10^-34 × 3×10^8/ 0.36

E= 55×10^-26 J

Hence the energy possessed by 0.36 meters wavelength radio waves is 55×10^-26 J

how many moles of solute are present in 50.0 ml of 0.20 m kno3

Answers

Answer: Volume = 50.0 mL in liters : 50.0 / 1000 = 0.05 L

n = M x V

n = 0.20 x 0.05

n = 0.01 moles of solute

Explanation:

The number of moles of solute are present in 50.0 mL of 0.20 M of KNO₃ solution is 0.01 moles.

How do we calculate moles?

Moles will be calculated by using the molarity formula because molarity is define as the no. of moles of solute present in per liter of the solution as:

M = n/V, where

M = molarity of KNO₃ = 0.2 M

V = volume of solution = 50mL = 0.05L

Moles will be calculated as:

n = (0.2)(0.05) = 0.01 moles

Hence required moles are 0.01 moles.

To know more about molarity, visit the below link:
https://brainly.com/question/26528084

Which substance should a student apply to the skin if he or she gets splashed with an acid?

Answers

First of all, you should be wearing proper PPE when handling acid, including a lab coat, large viton or butyl rubber gloves over nitrile gloves, apron, safety eye goggles (goggles!! not just safety glasses with an eyeshield), and face shield. You should be working in a fume hood with the sash closed in front of you as much as possible. This combination of engineering controls and PPE will help avoid a lot of big problems.

Need help with these three pls!!!!!

Answers

True because

False

True

1) true , 2) false , 3) true

How many atoms are there in 2 moles of helium?

Answers

Answer:

1 mole Of Helium = Weight of Helium/4Weight of Helium = 1*4 = 4 grams 1 mole of Helium contains 6.023*10²³ ( Avogadro number) atoms. Number of moles of in 4 grams of Hydrogen 4 grams is = given weight / molecular weight of Hydrogen (H₂) = 4/2 =2 Number of atoms/molecules in 2 moles of Hydrogen is (2*6.023*10²³) atoms. = 12.046*10²³ atoms.

(Hope this helps)

The number of atoms in 2 moles of helium is 1.204×10²⁴ atoms

From Avogadro's hypothesis,

1 mole of any substance = 6.02×10²³ atoms

Thus,

1 mole of helium = 6.02×10²³ atoms

With the above information in mind, we can obtain the number of atoms in 2 moles of helium as follow:

1 mole of helium = 6.02×10²³ atoms

Therefore,

2 moles of helium = 2 × 6.02×10²³ atoms

2 moles of helium = 1.204×10²⁴ atoms

Thus, we can conclude that 2 moles of helium contains 1.204×10²⁴ atoms

Learn more: https://brainly.com/question/24848191

what are the possible values for standard temperature and pressure

Answers

Answer:

0 °C and 1 Atm,

Explanation:

Standard Temperature and Pressure. Standard temperature is equal to 0 °C, which is 273.15 K.

Standard Pressure is 1 Atm, 101.3kPa or 760 mmHg or torr

What is El Nino and La Nina explained? Please help fast

Answers

Answer:

el nino: the boy

la nina: the girl

Explanation:

Answer:

el nino is dinosour la nino is fishcat

Explanation:

A community includes
A. all of the living organisms in a specific place at a specific time,
B. all plants, animals, minerals, and water in a specific place at a specific time,
C. only the plants in a specific place at a specific time.
D. only the animals in a specific place at a specific time.

Answers

Answer:
A. all living organisms in a specific place at a specific time

Answer:

answer: A. all of the living organisms in a specific place at a specific time

Explanation:

ASAP NEED HELP PLSSS
A gas occupying a volume of 3.75L at a pressure of 0.980 arm is allowed to expand at constant temperature until its pressure reaches 0.641 atm. What is the final volume of the sample?

Answers

Answer:

Volume = 5.73L

Explanation:

Data;

V1 = 3.75L

P1 = 0.980atm

P2 = 0.641atm

V2 = ?

This question involves the use of Boyle's law, which states that, the volume of a fixed mass of gas is inversely proportional to its pressure provided that temperature remains constant.

Mathematically,

V = kP, k = PV

P1V1 = P2V2 =P3V3=........=PnVn

P1V1 = P2V2

V2 = (P1 * V1) / P2

V2 = (0.980 × 3.75) / 0.641

V2 = 5.73L

The final volume of the gas is 5.73L