state the use of multimeters

Answer:

filtration

Explanation:

1.put the mixture in a beaker

2.add water to the beaker and stir to dissolve salt

3.filter using a filter paper to have sand as the residue

4.Evaporate the water to remain with salt crystals

Answer:

The answer is option A.

Compound

Hope this helps you

Answer : The initial concentration of HI and concentration of HI at equilibrium is, 0.27 M and 0.386 M  respectively.

Solution :  Given,

Initial concentration of H_2 and I_2 = 0.11 M

Concentration of H_2 and I_2 at equilibrium = 0.052 M

Let the initial concentration of HI be, C

The given equilibrium reaction is,

    H_2(g)+I_2(g)\rightleftharpoons 2HI(g)

Initially               0.11   0.11            C

At equilibrium  (0.11-x) (0.11-x)   (C+2x)

As we are given that:

Concentration of H_2 and I_2 at equilibrium = 0.052 M  = (0.11-x)

The expression of K_c will be,

K_c=\frac{[HI]^2}{[H_2][I_2]}

54.3=\frac{(C+2(0.058))^2}{(0.052)\times (0.052)}

By solving the terms, we get:

C = 0.27 M

Thus, initial concentration of HI = C = 0.27 M

Thus, the concentration of HI at equilibrium = (C+2x) = 0.27 + 2(0.058) = 0.386 M

Answer:

131.26 g

Explanation:

From the balanced equation,

2 moles of N₂H₄reacts with 1 mole of N₂O₄ to give 3 moles of N₂

Now number of moles of N₂H₄ present in 100 g N₂H₄ is n = 100 g/molar mass N₂H₄.

Molar mass N₂H₄ = 2 × 14.01 g/mol + 1 × 4 g/mol = 28.02 g/mol + 4 g/mol = 32.02 g/mol

n₁ = 100/32.02 = 3.123 mol

Also

Now number of moles of N₂O₄ present in 200 g N₂O₄ is n = 200 g/molar mass N₂O₄.

Molar mass N₂O₄ = 2 × 14.01 g/mol + 16 × 4 g/mol = 28.02 g/mol + 64 g/mol = 92.02 g/mol

n₂ = 200/92.02 = 2.173 mol

Since the mole ratio of N₂H₄  to N₂O₄ is 2 : 1, We require 2 × 2.173 mol N₂H₄  to react with 2.173 mole N₂O₄  

Number of moles of N₂H₄ required is 4.346. But the number of moles of N₂H₄  present is 3.123 so N₂H₄  is the limiting reagent.

So, from the equation, 2 moles of N₂H₄ produces 3 moles of N₂

Therefore number of mole N₂ = 3/2 moles of N₂H₄ = 3/2 × 3.123 mol = 4.6845 mol

From n = m/M where n = number of moles of nitrogen gas = 4.6845 mol and M = molar mass of nitrogen gas = 28.02 g/mol and m = mass of nitogen gas.

m = nM = 4.6845 mol × 28.02 g/mol = 131.26 g

So the mas of nitrogen gas produced is 131.26 g

Answer:

The main hazard related to organic peroxides are their fire and explosion hazards. ... It is the double oxygen of the "peroxy" group that makes organic peroxides both useful and hazardous. The peroxy group is chemically unstable. It can easily decompose, giving off heat at a rate that increases as the temperature rises.

Explanation:

Answer:

% purity of limestone = 96.53%

Explanation:

Question (4).

Weight of impure CaCO₃ = 25.9 g

Molecular weight of CaCO₃ = 40 + 12 + 3(16)

                                              = 100 g per mole

We know at S.T.P. number of moles of CO₂ = 1 and volume = 22.4 liters

From the given reaction, 1 mole of CaCO₃ reacts with 1 mole or 22.4 liters of

CO₂.

∵ 22.4 liters of CO₂ was produced from CaCO3 = 100 g

∴ 1 liter of CO₂ will be produced by CaCO₃ = [tex]\frac{100}{22.4}[/tex]

∴ 5.6 liters of CO₂ will be produced by CaCO₃ = [tex]\frac{100\times 5.6}{22.4}[/tex]

                                                                              = 25 g

Therefore, % purity of CaCO₃ = [tex]\frac{\text{Weight calculated}}{{\text{Weight given}}}\times 100[/tex]

                                                 = [tex]\frac{25}{25.9}\times 100[/tex]

                                                 = 96.53 %

Answer:

C: The surroundings heat up and the system decreases in volume.

D: The surroundings heat up and the system does not change volume.

B: The surroundings heat up and the system expands in volume.

A: The surroundings get cold and the system decreases in volume.

Explanation:

The most exothermic reactions are those that release heat, that is to say, they give up the heat as it cools and the surroundings heat up.

As for endothermics, that is, those that absorb or capture the heat of the medium, they are variables that cool the environment that surrounds them and increase their internal temperature

Answer: Hg +2

Explanation:

Hg+2 is formed when mercury loses two electrons.

Hg  ------>  Hg +2  +  2 e-

Answer:

Hg+2 (D) is the correct answer

Explanation:

the person above me is correct, hope this helps, have a good one

Answer:

Both gives hydroxides, but

Calcium reacts with water to give calcium hydroxide Ca(OH)2. this product is slightly soluble in water.

Aluminium  is less reactive than Ca, so it reacts with only steam, to give aluminium hydroxide Al(OH)3. This product is insoluble in water.

Answer:

idk but i tryed

Explanation:

The simplest way to use the periodic table to identify an element is by looking for the element’s name or elemental symbol. The periodic table can be used to identify an element by looking for the element’s atomic number. The atomic number of an element is the number of protons found within the atoms of that element.

There are approximately 5.621 x 10^24 lithium atoms in 9.35 moles of lithium.

To determine the number of atoms in 9.35 moles of lithium, we can use Avogadro's number, which is the number of particles (atoms, molecules, etc.) in one mole of a substance. Avogadro's number is approximately 6.022 x 10^23 particles per mole.

First, we need to calculate the total number of lithium atoms in 9.35 moles of lithium:

Number of lithium atoms = (9.35 mol) x (6.022 x 10^23 atoms/mol)

Number of lithium atoms = 5.621 x 10^24 atoms

In chemistry, a mole is a unit of measurement used to express the amount of a substance. One mole of a substance is defined as the amount of the substance that contains the same number of particles as there are atoms in 12 grams of pure carbon-12. This number is known as Avogadro's number and is approximately 6.022 x 10^23 particles per mole.

For more question on lithium atoms click on

https://brainly.com/question/30377436

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Answer:

-1,300 kJ

Explanation:

P₄  +  3 O₂  ⇒  P₄O₆     ΔH = -1,640.1 kJ    (EQ 1)

P₄O₁₀  ⇒  P₄  +  5 O₂    ΔH = 2,940.1 kJ    (EQ 2)

These are the equations you are given.  You need to make these equations into the equation below.

P₄O₆  +  2 O₂  ⇒  P₄O₁₀  (end equation)

Look at the product side of the end equation.  You need to produce P₄O₁₀.  In the EQ 2, P₄O₁₀ is on the reactant side.  Flip the equation.  Since you flipped the equation, the enthalpy will have the opposite sign.

P₄  +  5 O₂  ⇒  P₄O₁₀    ΔH = -2,940.1 kJ

On the reactant side of the end equation, you need P₄O₆ and 2 O₂.  First, rearrange the equation so that P₄O₆ is on the right side.  In EQ 1, P₄O₆ is on the product side.  Flip the equation.  Like the last one, the sign will change.

Now, cancel out all possible values.  P₄ will cancel out since there is one on each side of the equation.  Since there is 5 O₂ on one side and 3 O₂ on the other, subtract the two and put the remainder on the side of the larger value.

P₄  +  5 O₂  ⇒  P₄O₁₀    ΔH = -2,940.1 kJ

P₄O₆  ⇒  P₄  +  3 O₂     ΔH = 1,640.1 kJ    

P₄O₆  +  2 O₂  ⇒  P₄O₁₀

This should be the resulting equation.  Now, add the two enthalpies together to find the overall enthalpy.

-2,940.1 kJ  +  1,640.1 kJ  = -1,300 kJ

The overall enthalpy is -1,300 kJ.

-867.7Answer:

Explanation:

-867.7

Answer:

Shifts to the left

Explanation:

Usually when adding HCl to a system it reduces stress causing the equilibrium to go to the left

Answer:

18.015

Explanation:

That other guy is on something, their answer didn't relate to the question at all. Anyways.. Jesus loves YOU!

Here is the answer in picture form

Answer:

64g of O2.

Explanation:

We'll begin by calculating the number of molecules in 73g if HCl.

This is illustrated below:

From Avogadro's hypothesis, we understood that 1 mole of any substance contains 6.02×10²³ molecules. This implies that 1 mole of HCl also contains 6.02×10²³ molecules

1 mole of HCl = 1 + 35.5 = 36.5g

Thus, if 36.5g of HCl contains 6.02×10²³ molecules, then 73g of HCl will contain = (73 x 6.02×10²³)/36.5 = 1.204×10²⁴ molecules.

Therefore, 73g of HCl will contains 1.204×10²⁴ molecules.

Now, we shall determine the mass of oxygen that will contain 1.204×10²⁴ molecules.

This can be obtained as follow:

1 mole of O2 = 16x2 = 32g

32g of O2 contains 6.02×10²³ molecules.

Therefore, Xg of O2 will contain 1.204×10²⁴ molecules i.e

Xg of O2 = (32 x 1.204×10²⁴)/6.02×10²³

Xg of O2 = 64g

Therefore, 64g of O2 will contain the same number of molecules (i.e 1.204×10²⁴ molecules) in 73g of HCl.

Answer:

23 protons, 23 electrons, 33 neutrons

Explanation:

I don't know why my answer got deleted but no worries, I can answer again. The number of protons and electrons is equal to the atomic number which is 23 and the number of neutrons is 56 - 23 = 33 because atomic mass denotes the number of protons and neutrons.

Answer:

when high-energy particles from the sun are trapped by earth's magnetic field

Explanation:

it is produced by a "depression" in the Earth's magnetic field in that area, caused by the fact that the center of the Earth's magnetic field is deviated from its geographic center by 450 km. Such an anomaly is thought by some to be a side effect of a Geomagnetic Reversal. These radiation belts originate from the Earth's intense magnetic field that is the product of their rotation. That field traps charged particles (plasma) from the Sun (solar wind), as well as charged particles that are generated by interaction of the Earth's atmosphere with cosmic radiation and high-energy solar radiation.

Answer:

D

Explanation:

its the last one

Answer:

92

98

35

35

Explanation:

Answer:

Medical: Magnets are used for the RMN, which uses waves and magnets to create images of the body, this process is really complex because is deeply related to quantum mechanics, so i will not dive in the topic.

Security: You can attach a magneto to a sensor, and when the magnet detects a metal, a current flows to the sensor and it can make a noise. This system is used to detect if someone has something of metal (like a knife for example) and a similar system is used to detect land mines or metals under the ground, which can be related to "route finding".

Sorting steel: When you have a mix of different metals, some of them will be attracted to the magnet and others not. An example where this is used is when you have a piece of steel with impurities, you can melt it and use a magnet to only grab the steel and leave most of the impurities.

Recycling. Big magnets are used to manage large pieces of steel that may be difficult or dangerous to handle by hand, for example. in order to move old cars and objects of similar size of steel, a big magnet is used.

Music: Modern instruments like electric guitars or electric basses, use magnets in the pickups: The magnet detects the movement of the strings, and this creates a current in a copper wire that is winded around the magnets, and that current then is transformed into sound by the amplifier.

Answer:

Neon molecule does not exist.

Explanation:

Neon is denoted by Ne which is noble gas. According to the "Molecular Orbital Theory", only those molecules exist that have a positive bond order and molecules with no bond or negative bond order cannot exist.

Answer:

Rutherford's atomic model explained how the electrons surrounded the nucleus of protons and neutrons. His model showed how J. J. Thomson's Plum Pudding model was incorrect.

Answer:Rutherford model of an atom shows that an atom is mostly an empty space,with electrons orbiting a fixed positively charged nucleus in set.

Explanation:

Answer:

H % = 11.11%

O % = 88.89%

Explanation:

atomic weight of H = 1

atomic weight of O = 16

each molecule of water contains 2 atoms of H and one atom of O

hence molecular weight of water = 18

H % = 2 x 100/18 = 11.11%

O % = 16 x 100/18 = 88.89%

Answer:

-H= 11.19%

-O= 88.81%

Explanation: the answer above mine is incorrect!,  i just did it and i got it right, the answer is h= 11.19% and O= 88.81% hope it helps!

Answer:

series means current same

parallel means potential same

Answer:

VSEPR molecular shapes are the substances from the laboratory operation that have more than one central atom.

Explanation:

Molecular shapes from VSEPR

Explanation:

The reason is VSEPR theory, it considers electrons, involved in bond formation as the key part. The pairs of electrons around a central atom, they may be in  sigma bonds, pi bonds, or lone pairs, are always in proximity with the positive nucleus and  as far as possible from each other. Therefore, only the lone pairs on the central atom are taken into consideration when predicting molecular shape.

H2O2 , C2O4,  CH3OH, CH3NH2

substances from the lab activity have more than one central atom

Answer:

3 FeCl3 + H2S = 2 FeCl2 + S + 2 HCl

Explanation:

Fe goes form +3 to +2

S goes from -2 to 0

H and Cl are spectator ions

Fe3+ + 1e-= Fe2+

H2S = S + 2 H+ + 2e-

3 Fe3+ + H2S = 2 Fe2+ + S + 2 H+

3 FeCl3 + H2S = 2 FeCl2 + S + 2 HCl

Answer:

destroyed.

transferred.

Explanation:

hehe

Answer:

Your answer would be destroyed and Transferred.

Explanation:

The reason why is because energy is never created or destroyed because it is just transferred to different forms of energy. Suich as a ball at the top of a hill. It's not moving, so it has potential energy, (potential energy is energy that is stored) and let's say that some wind comes through and gives that ball a push, so now the ball is moving and is going downhill. now the ball has kinetic energy because it was transferred to a moving energy from a stored energy.

Answer: Wheat flour, edible oil, egg white, lettuce preservative, meat or poultry marinade, vegetable antibacterial wash.

Explanation:

hydrogen peroxide is used as a bleaching agent in some food

I hope this helped