helpppppp plzzzzz lol​

i think the answer is b) i.e. Switch....

according to me ammeter and battery are already there...

The frequency : f = 4.478 x 10¹⁴ /s

Given

wavelength = 670 nm = 670 x 10⁻⁹ m = 6.7 x 10 ⁻⁷ m

Required

The frequency

Solution

Wavelength : from the crest to the crest of the next wave or the trough to the trough

Frequency (f): number of waves in one second

Can be formulated :

 v = λ x f

f = v / λ

So the frequency is inversely proportional to the wavelength

v = 3 x 10⁸ m/s(speed of light)

Input the value :

f = 3 x 10⁸ m/s : 6.7 x 10 ⁻⁷ m

f = 4.478 x 10¹⁴ /s

Answer:

By far the most abundant volcanic gas is water vapor, which is harmless. However, significant amounts of carbon dioxide, sulfur dioxide, hydrogen sulfide and hydrogen halides can also be emitted from volcanoes.

Answer:

5.95 moles

Explanation:

No of moles = given mass / molar mass

No of moles = 137/23

= 5.95 moles

Answer:

A

Explanation:

In a galvanic cell, energy is produced by spontaneous chemical processes.

The cathode and anode of this cell will depend on the relative position of the two metals in the electrochemical series.

Aluminium is higher in the electrochemical series so aluminium will be the anode. Silver is lower in the electrochemical series so silver will be the cathode.

Recall that oxidation (electron loss) occurs at the anode while reduction (electron gain) occurs at the cathode.

The half-reactions for the galvanic cell with aluminum and gold electrodes is [tex]\mathbf{Al_{(s)}\to Al^{3+} _{(aq) } + 3e^- \ and \ Au^+_{(aq)} +e^- \to Au_{(s)}}[/tex]

Galvanic cells are electrochemical cells that generate electrical energy by the spontaneous activity in the oxidation-reduction (redox) reaction process.

The position of the metals if they are going to be at the cathode or at the anode relatively depends on the position with which they find themselves in the electrochemical series. The higher metal will be the anode and the lower metal in the electrochemical series will be the cathode.

Since aluminum is higher than gold on the electrochemical series, then:

Therefore, the half-reactions for the galvanic cell with aluminum and gold electrodes is [tex]\mathbf{Al_{(s)}\to Al^{3+} _{(aq) } + 3e^- \ and \ Au^+_{(aq)} +e^- \to Au_{(s)}}[/tex]

Learn more about Galvanic cells here:

https://brainly.com/question/25606597

Answer:

+ 3

Ex planation:

Al3+ indicates an ion of aluminum having a charge of + 3. I.e., since an aluminum atom normally has 13 protons and 13 electrons, this ion has 10 electrons (-10 charge) and 13 protons (+ 13 charge) giving it a charge of + 3 (-10 + 13 = +3).

hope this helps!

Answer:

Heat packs that contain iron and water packets: Exposing the solution to air results in the oxidation of the iron (creates rust). The oxidation of the iron is an exothermic process. Heat packs that contain supersaturated sodium acetate: These are reusable, the packs are boiled to dissolve sodium acetate.

Explanation:Thanks for asking question

Answer:

0.776 ×10²³ atoms of oxygen

Explanation:

Given data:

Mass of Al₂CO₃ = 10.0 g

Number of atoms of oxygen = ?

Solution:

Number of moles of Al₂CO₃:

Number of moles = mass/molar mass

Number of moles = 10.0 g/233.99 g/mol

Number of moles = 0.043 mol

1 mole of Al₂CO₃ contain 3 mole of oxygen.

0.043 ×3 mol = 0.129 mol

Number of atoms of oxygen:

1 mole contain 6.022×10²³ atoms

0.129 mol × 6.022×10²³ atoms / 1mol

0.776 ×10²³ atoms of oxygen

Answer: Convection Currents

Explanation:

Due to the different   temperature occurring at the  upper and lower layers  of the mantle, it causes  heat transfer to occur. One of such heat transfer is the Convection currents which causes  warmer, less dense rock material in the core to rise through the mantle. Also, the cooler rocks in the higher mantle move slowly towards the core.The movement caused by these  Convection current in the Earth are  called plate tectonics which are responsible for earthquakes and volcanoes.

Explanation:

There is a limit to different things we encounter around the universe due to a lot of reasons.

To overcome these barriers, some catalysts that are not readily available are needed. This reduces the combination of some atoms in nature.

This and many more reasons limits the combination of chemical substances.

There is a limit to different things we encounter around the universe due to a lot of reasons:

So, for a chemical reaction to occur there are certain parameters that need to taken into consideration for a chemical reaction to actually takes place.

Learn more:

brainly.com/question/21568405

A displacement reaction is the one wherein the atom or a set of atoms is displaced by another atom in a molecule. For instance, when iron is added to a copper sulphate solution, it displaces the copper metal.

A + BC → AC + B

The above equation exists when A is more reactive than B.

A and B have to be either:

Halogens where C indicates a cation.

Different metals wherein C indicates an anion.

[tex]\textsf{what is a displacement reactions?   }[/tex]      

[tex]\large \underbrace{ \underline{ \sf Displacement \: reaction}}[/tex]

The reaction in which more reactive element replace a less reactive element from its compound is called displacement reaction.

Ex:-

[tex]\bold{\large Zn+HCl \longrightarrow ZnCl_2+H_2}[/tex]

Answer:

Its in the Explanation

Explanation:

Here's what I got.

Aluminium-27 is an isotope of aluminium characterized by the fact that is has a mass number equal to  

27

.

Now, an atom's mass number tells you the total number of protons and of neutrons that atom has in its nucleus. Since you're dealing with an isotope of aluminum, it follows that this atom must have the exact same number of protons in its nucleus.

The number of protons an atom has in its nucleus is given by the atomic number. A quick looks in the periodic table will show that aluminum has an atomic number equal to  

13

.

This means that any atom that is an isotope of aluminum will have  

13

protons in its nucleus.

Since you're dealing with a neutral atom, the number of electrons that surround the nucleus must be equal to the number of protons found in the nucleus.

Therefore, the aluminium-27 isotope will have  

13

electrons surrounding its nucleus.

Finally, use the known mass number to determine how many neutrons you have

mass number

=

no. of protons

+

no. of neutrons

no. of neutrons = 27 − 13 = 14

Your welcome :)

Surface waves travel across the Earth’s surface and body waves travel through the Earth’s interior.

there you go :)

Answer:

Plasma.

Explanation:

In science, matter can be defined as anything that has mass and occupies space. Any physical object that is found on earth is typically composed of matter. Matter are known to be made up of atoms and as a result has the property of existing in states. The three (3) classical states of matter are;

I. Solid.

II. Liquid.

III. Gas

Plasma can be defined as a state of matter in which the electrons temporarily separate from the protons and as a result, it is generally referred to as the fourth (4th) state of matter due to its superheated nature.

Answer:

I think that the first one is right(A)

Answer:

A,B,C

Explanation:

Answer:

481.6x10^23

Explanation:

Answer:

[tex]\boxed {\boxed {\sf About \ 4.82 *10^{24} \ atoms \ K_2CrO_4}}[/tex]

Explanation:

To convert from moles to atoms, Avogadro's Number must be used.

This number tells us how many particles (atoms, molecules, ions. etc.) in 1 mole of a substance. In this case, it is atoms of potassium chromate (K₂CrO₄) in 1 mole.

[tex]6.022*10^{23} \ atoms \ K_2CrO_4 / 1 \ mol \ K_2CrO_4[/tex]

Use this number as a fraction.

[tex]\frac{6.022*10^{23} \ atoms \ K_2CrO_4}{1 \ mol \ K_2CrO_4}[/tex]

Multiply by the given number of moles (8.00).

[tex]8.00 \ mol \ K_2CrO_4 *\frac{6.022*10^{23} \ atoms \ K_2CrO_4}{1 \ mol \ K_2CrO_4}[/tex]

The moles of potassium chromate will cancel.

[tex]8.00 *\frac{6.022*10^{23} \ atoms \ K_2CrO_4}{1}[/tex]

The denominator of 1 can be ignored.

[tex]8.00 *(6.022 *10^{23} \ atoms \ K_2CrO_4)[/tex]

Multiply.

[tex]4.8176*10^{24} \ atoms \ K_2CrO_4[/tex]

The original measurement of moles (8.00) has 3 significant figures, so we must round our answer to 3 sig figs.

For the number we calculated, that is the hundredth place. The 7 in the thousandth place tells us to round the 1 up to a 2.

[tex]4.82 *10^{24} \ atoms \ K_2CrO_4[/tex]

There are about 4.82* 10²⁴ atoms of potassium chromate in 8.00 moles.

Answer:

It is a Physical change, have a great day :)

Explanation:

A chemical change is a permanent change. A Physical change affects only physical properties i.e. shape, size, etc. ... Some examples of physical change are freezing of water, melting of wax, boiling of water, etc. A few examples of chemical change are digestion of food, burning of coal, rusting, etc.

Answer:

B

Explanation:

Answer:

17

Explanation:

the atomic mass is away protons + neutrons, electrons are neglatable.

Answer:

PRACTICE MULTIPLE CHOICE QUESTIONS FROM UNIT 10

1.) A cylinder is filled with 2.00 moles of nitrogen, 3.00 moles of argon, and 5.00 moles of helium. If

the gas mixture is at STP, what is the partial pressure of the argon?

(A) 152 torr (B) 228 torr (C) 380. torr (D) 760. torr

2.) Compared to the average kinetic energy of 1 mole of water at 0 oC, the average kinetic energy

of 1 mole of water at 298 K is

(A) the same, and the number of molecules is the same

(B) the same, but the number of molecules is greater

(C) greater, and the number of molecules is greater

(D) greater, but the number of molecules is the same

3.) If the pressure on a given mass of gas in a closed system is increased and the temperature

remains constant, the volume of the gas will

(A) decrease (B) increase (C) remain the same

4.) Which gas has approximately the same density as C2H6 at STP?

(A) NO (B) NH3 (C) H2S (D) SO2

5.) At a temperature of 273 K, a 400. milliliter gas sample has a pressure of 760. millimeters of

mercury. If the pressure is changed to 380. millimeters of mercury, at which temperature will

this gas sample have a volume of 551 milliliters?

(A) 100 K (B) 188 K (C) 273 K (D) 546 K

Get the answers to these questions

Back to the Unit 10 Old Tests Pag

Answer:

A.Magnesium

Explanation:

Answer:

magnesium

Explanation:

Answer:

After jumping to the higher energy level also called the excited state the excited electron would be in a less stable position, so it would quickly emit a photon to relax back to a lower, more stable energy level.

Answer:

They have direct relationship and larger wave energy.

Answer:

Its D on edge

Explanation:

i took the test

Answer:

Viscosity

Explanation:

Viscosity is how thick a liquid is due to internal friction.

Answer:

c. protons and neutrons are found in the nucleus

d. protons and neutrons have approximately the same mass

Explanation:

There are three fundamental particles within an atom which are the protons, neutrons and electrons.

The protons are the positively charged particles within an atom

Neutrons do not carry any charges

Electrons are the negatively charged particles.

Geothermal energy is heat produced by the Earth itself. It is a resource that may be gathered for human use and is renewable.

The correct option is (D) Thermal energy absorbed by the Sun at the Earth's crust

Learn more about the Geothermal energy with the help of the given link:

https://brainly.com/question/1061324

#SPJ1

Answer:

A physical change.

Explanation:

Have a wonderful day!