Plz i wanna those answers click on the photo to see all the question they are 2 queastions part A and B

Answer:

Various limitations of Mendeleev's periodic table are:-

Position of hydrogen - he couldn't assign a correct position to hydrogen as it showed properties of both alkali and halogens .

Position of isotopes - he considered that the properties of elements are a function of their atomic masses. Hence isotopes of a same element couldn't be placed.

In the d-block , elements with lower atomic number were placed before higher atomic number.

Explanation:

Answer:

 2Fe +  3CuSO₄  →  Fe₂(SO₄)₃   +  3Cu

Explanation:

The reactants are:

   Iron  = Fe

  Copper (II) sulfate solution = CuSO₄

The reaction is given as:

            Fe +  CuSO₄  →  Fe₂(SO₄)₃   +  Cu

This is a single displacement reaction;

  Now let us balance the equation;

             aFe +  bCuSO₄  →  cFe₂(SO₄)₃   +  dCu

Conserving Fe;

                       a  = 2c

  Conserving  Cu;

                      b  = d

  Conserving S;

                      b  = 3c

  Conserving O;

                    4b  = 12c  

let b  = 1;

    c = [tex]\frac{1}{3}[/tex]  

     d  = 1

     a  = [tex]\frac{2}{3}[/tex]

Multiply through by 3 to get whole numbers;

  a  = 2, b = 3, c  = 1 and d  = 3

           2Fe +  3CuSO₄  →  Fe₂(SO₄)₃   +  3Cu

Answer:

down syndrome

Explanation:

Answer:

the best answer would be A

Explanation:

cause it contains a red colored compound.

Answer:

A. electric field

Explanation:

took test

Answer:

electric field

Explanation:

Answer:

I believe the amswer is a hope this helps

Answer:

c

Explanation:

hope you can redo it to get it right

Answer:

B) number of electrons

Explanation:

The two species:

          K+   and Cl- have the same number of electrons.

A neutral atom of K has 19 electrons

A neutral atom of Cl has 17 electrons

Now,

 To form K+, K will have to lose an electron and then the number of electrons becomes 18

To form Cl-, Cl will have to gain an electrons and then the number of electrons becomes 18

So, therefore, the number of electrons on both species is 18

Answer:

1.2 × 10 to the power 25 . atoms of iron divide by a line 6.022× iron atoms per mole =~ 20 moles

Answer:

Q = 3440Kj

Explanation:

Given data:

Mass of gold = 2kg

Latent heat of vaporization = 1720 Kj/Kg

Energy required to vaporize 2kg gold = ?

Solution:

Equation

Q= mLvap

It is given that heat required to vaporize the one kilogram gold is 1720 Kj thus, for 2 kg

by putting values,

Q= 2kg ×  1720 Kj/Kg

Q = 3440Kj

Answer:

They break and reform bonds

Explanation:

Chemical reactions basically refer to the transformation of a substance (reactant) to another substance (products).

So we have;

Reactant --> Product

They can go in just one direction.

This option is wrong, because there are reversible reactions which can go in both directions. That is reactants reactants to form products and products react to form reactants.

They occur only in science labs.

This is wrong because chemical reactions occur in our day to day activities. An example is rusting.

They break and reform bonds.

This option is correct. There is breaking of bonds in the reactants and forming of new bonds in the products.

They create new elements

Atoms or elements are not created nor destroyed in chemical reactions so this option is wrong.

Answer:

2200J

Explanation:

Given parameters:

Specific heat of aluminum  = 0.88J/g°C

Mass of nugget  = 50g

Initial temperature  = 20°C

Final temperature  = 70°C

Unknown:

Quantity of heat required for the heating = ?

Solution:

To solve this problem, we use the expression below;

       H  = m c Δt

H is the quantity of heat

m is the mass

c is the specific heat capacity

Δt is the change in temperature

        H  = 50 x 0.88 x (70 - 20) = 2200J

Answer:

the answer is D: explanations of why the puck slides faster

Explanation:

A Girl in Brainly Banned/Removed the answer i had put the first time, Brainly claims she removed my answer because i was violating community guidelines such as cheating or plagiarism. The reason for putting my answer was because i took a test, i got it right and i want other people to take a test and get the answer right. Im trying to help:).

so katie if your reading this, try next time to mind your own business

Answer:d

Explanation:

Answer:

Drain Cleaner

Explanation:

I just took the test and got it right :)

drain cleaner............................

Answer:

B

Explanation:

Both plain and plateau have flat surfaces. However, a plain is located in a low-lying area while a plateau is located on an elevated area. In essence, a plateau can be viewed as an elevated plain or a plain that is bordered by cliffs.

The correct option is B.

Answer:

The Voltaic Cell

Explanation:

Answer: A

Explanation: i just took the test :)

Answer:

Deforestation

Explanation:

The value of softwood means that large areas of Russia's taiga have been cleared: deforestation is occurring at a rate of 12 million hectares per year (2014). As much as half of the logging in the far east of Siberia is illegal

Answer:

deforestation

Explanation:

and tectonic plates

Answer:

atmospheric circulation

Explanation:

Atmospheric circulation occurs  because the Sun heats the Earth more at the equator than at the poles.

Warm air is known to rise at the tropics which lies closer to the equator and moves towards the poles. Atmospheric circulation is driven by the rotation of the earth.

The air cools and flows back towards the Equator to be warmed up again. A sort of convection current is thereby set up.

Answer:

Radio waves are a type of electromagnetic radiation best-known for their use in communication technologies, such as television, mobile phones and radios.

Answer:

the number of moles of atom is 0.91584

Answer: 1.01 atomic mass units or amu

Explanation:

Answer:

i think right artrium but not full aure

1 kg = 1000g

1l = 1000cm3

therefor

kg/l = 1000g/1000cm3

cancel the zeros

kg/l = g/cm3 demonstrated

Answer:

Part A

i) A property of water that contributes to its movement through capillary tubes is adhesion, which is the capacity of water to stick to other surfaces

ii) Water has a polar molecular structure as such the hydrogen present in the water molecules form bonds with the oxygen present in the silicon oxide molecules from which the capillary tube is normally made

Part B.

i) From the given graph, the function appears to have a vertical asymptote at x = 0, therefore, the plant can grow infinitely tall

ii) The molecular structure of the vessel can be modified such that the walls incorporate more oxygen molecules per mole which will increase the number and the strength of the hydrogen bond between the water molecules and the walls of the plant vessel and therefore, increase the capillary action, the water height and the maximum height of the tree

Explanation:

Answer:

The answer is: A

Explanation:

The wave-like contractions are to be considered a physical change as they do not take part in the breaking-down of the food. The peptidase is a chemical change because it is used to chemically break down the food to retrieve nutrients and such.

Answer:

thermometer

Explanation:

The most important tool to use when collecting data relating to how thermal energy affects metals would be the thermometer.

The thermometer is an instrument used to measure temperatures and the temperature of a body is a measure of the amount of thermal energy present in the body.

In order to obtain data relating to how thermal energy affects metals, the most important variable to take note of would be the thermal energy of the metals and this can only be done by the thermometer.

Answer:

Yes.

Explanation:

Yes, elevation play a great role and has the ability to protect homes from natural disasters such as flood and tsunami etc. The residents build a hard structure of wall along the beach that would prevent a tsunami from reaching the community and also built homes at higher elevation. The residence built it with the help of government and this wall is also effective in reducing the erosion of the beach.

Answer:

1. Yes elevation does play a factor if the house was higher i feel like it wouldnt get as damaged  

2.  Yes they could build a high enough wall that it would take most of the impact away from the houses, you would build it with the thickest peice of wood that you could find and use long screws and cement the  wood into the ground.  

3. The wall will also help from erosion

Explanation: i got it right on my project.

Answer:

there is no image

Explanation:

can you maybe ask the question again with the image?

Answer:

put an image please i don't understand

Answer:

E = 1.89×10⁻¹⁹ J

Explanation:

Given data:

Wavelength of photon = 105 nm (105 ×10⁻⁹ m)

Energy of photon = ?

Solution:

Formula:

E = hc/λ

h = plancks constant = 6.63×10⁻³⁴ Js

c = speed of wave = 3×10⁸ m/s

by putting values,

E =  6.63×10⁻³⁴ Js ×3×10⁸ m/s / 105 ×10⁻⁹ m

E = 19.89×10⁻²⁶ J.m / 105 ×10⁻⁹ m

E = 0.189×10⁻¹⁷ J

E = 1.89×10⁻¹⁹ J