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Question is under topic, solid state chemistry and boarders on pontential,kinetic energy newton's law etc

1  A ball of mass 2.5 kg is pushed along a frictionless surface with a constant force of 15 N applied. Calculate the acceleration of the ball. Express your answers in m/s2.

 

 2  An electron is accelerated in a cathode ray tube and moves at a velocity of 3.0*10^6 km/hour. Calculate the kinetic energy of the electron. You can find the mass of an electron on the Table of Constants in the handouts. Express your answer in units of Joules (J).

 

 

3  An apple weighing 100 grams is on a shelf at a height of 180 cm from the floor. A child bumps into the shelf and the apple falls onto a nearby table. The table is at a height of 1 m from the floor. Calculate the change in potential energy of the apple between its initial state (on the shelf) and final state (on the table). The gravitational field on earth is 9.81 m/s2. Express your answer in units of Joules (J).

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The thermite reaction, used to weld rails together in the building of railroads, occurs when iron(III) oxide (Fe2O3) reacts with

The thermite reaction, used to weld rails together in the building of railroads, occurs when iron(III) oxide (Fe2O3) reacts with elemental aluminum to produce aluminum oxide (Al2O3) and elemental iron.

(a)Write a balanced equation for this reaction, using any correct set of coefficients. Depict the reaction arrow () as '->'.

 

 

b)Calculate the mass of iron metal (in grams) that can be prepared from 150 grams of aluminum and 250 grams of iron(III) oxide.

 

 

c)Write the balanced chemical equation using the lowest possible whole number coefficients.

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Dalton's Theory Mistakes: Which Ones Was He Wrong With?

I know he was wrong with his theories about all atoms of the same element being identical and atoms being indivisible. But wasn't he also wrong with his theory that "Atoms of different elements may combine with each other in a fixed, simple, whole number ratios to form compound atoms", because atoms do not always combine in simple, whole number ratios when forming a compound (seen in sucrose)?
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No one has been able to help me with my question yet? Maybe you can? Please I'd really appreciate it? Chemistry Question

The question is in the photo

 

But I Have been trying to seek for an answer for hours, however no one is able to help me

 

Can someone please help me? I'd really appreciate it :( 

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No one has been able to help me with my question yet? Maybe you can? Please I'd really appreciate it? Chemistry Question

Question is in the photo. 

 

I've been trying to ask for help on this question for hours, but no one has seem to be able to help me? 

 

I'd really appreciate it if someone could? :( 

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DE BROGLIE CONCEPT OF MATTER WAVES

De broglie concept of matter waves

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determine the ground stare term of vanadium+3?

Determine the ground state term for V3+.

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The wave number of the light emitted by a certain source is 2 x 10 6 m-1. Then what is the wave length of this light ?

The wave number of the light emitted by a certain source is 2 x 10 6 m-1. Then what is the wave length of this light ?

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Avogardro constant calculation. I need help answering a particular question and others similar.

How would i work out this question?

The mass of one atom of 12C is 1.99x10-23 g. Use this information to calculate a value for Avogadro constant. Show your working. (2)

Thank you :)

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plz can anyone read my lab report n tell me if it´s correct?my whole chimestry course depends on it :( plzzz?

plz can anyone read my lab report n tell me if it´s correct?my whole chimestry course depends on it :( plzzz?  

 Heating of bicarbonate
1. Introduction
purpose:
The purpose of this lab is for us to find out which reactions are correct when sodium bicarbonate heats .
theory:
In this lab , we need to know how to find molar masses and convert it into molecules. We also need to know how to write a balanced chemical equation .
Amount of substance formula n = m / M,
Lot formula m = n * M ,
Molar mass formula M = n / m
Possible chemical reactions:
Proposal 1: NaHCO3 -> NaOH ( s ) + CO2 ( g )
Proposal 2: NaHCO3 -> Na2O ( s ) + H20 ( g) + CO2 ( g )
Proposal 3: NaHCO3 -> Na2CO3 ( s ) + H2O ( g) + CO2 ( g )

2nd execution:
materials:
crucible , crucible tongs , wave, Burner , Spoon , tripod .
Chemicals : 1.50 g NaHCO3 ( s ) .

execution:
The lab began with the reaction formulas balanced and then weighed empty crucible to know how much it weighs without sodium bicarbonate. Afterwards added 1.50 g of sodium bicarbonate ( NaHCO3) in the crucible . Thereafter treforten for holding crucible of burners. Moreover, with the help of the wave was measured measured the mass of the product. How would it know which of the reactions were in the best, and it did using to calculate the molar mass and mass.

3rd results:
Balancing the reactions are:
1. NaHCO3 -> NaOH ( s ) + CO2 ( g )
NaHCO3 -> NaOH ( s ) + CO2 ( g )
2nd NaHCO3 -> Na2O ( s ) + H2O ( g) + CO2 ( g )
2NaHCO3 -> Na2O ( s ) + H2O ( g ) +2 CO2 ( g )
3rd NaHCO3 -> Na2CO3 ( s ) + H2O ( g) + CO2 ( g )
2NaHCO3 -> Na2CO3 ( s ) + H2O ( g) + CO2 ( g )

M (NaHCO3 ) : Na = 22.1 g, H = 1.01 g , C = 12.0 g , O = 16.0 g * 3 = 83.11 g / mol
m (NaHCO3 ): 1.50 g
n (NaHCO3 ): 1.50 g / 83.11 g / mol = 0.01804 = about 0.02 moles
After the reaction mass was : 0.6 g
Bräkningar :
1. NaHCO3 -> NaOH ( s ) + CO2 ( g )
M (NaOH ) = Na = 22.1 g + O = 16.0 g + H = 1.01 g = 39.11 g / mol

m (NaOH ) = 0.6 g

n = 0.6 g / 39.11 g / mol = 0.015341 = about 0.02 moles
Amount ( mol) is equal on both sides .

2nd 2NaHCO3 -> Na2O ( s ) + H2O ( g ) +2 CO2 ( g )
M ( Na2O ) = 22.1 g * 2 + O = 16.0 g = 60.2 g / mol
m ( Na2O ) = 0.6g
n ( Na2O ) = 0.6 g / 60.2 g / mol = 0.009966 = approximately 0.011 mol

number of moles is double led so great on the left side . In order for us to know if it is the right reaction , so we need to multiply by (2 ) to get the same number of moles on both sides -> n ( Na2O ) = 0.009966 * 2 = 0.019932 = approximately 0.021 mol

3rd 2NaHCO3 -> Na2CO3 ( s ) + H2O ( g) + CO2 ( g )
M (Na2CO3 ) = 22.1 * 2 + 1.01 + 16.0 * 3 = 93.2 g / mol
m (Na2CO3 ) = 0.6g
n (Na2CO3 ) = 0.6 g / 93.2 g / mol = 0.0643777 = approximately 0.0064 moles

The number of moles is double led so great on the left side . Then we multiply by (2 ) to get the same number of moles of both sides.
n (Na2CO3 ) = 0.0643777 * 2 = 0.0128755 = about 0.013 moles
Calculations of the amount of substance has been shown that heating of potassium hydrogen carbonate takes place according to reaction formulas 3rd

discussion :
When sodium bicarbonate is heated , there was formed sodium carbonate, water and carbon dioxide. After the heating, the less mass as water and carbon dioxide is released , which means that they changed their aggregationsformler and became gases. The net amount calculated by the mass was already known and molar mass could be calculated, then it could take to be sorted out, please calculate the amount of substance for both sides and see which one has the most equal amount of substance with potassium bicarbonate. When the calculations were made , we did so with the form = n = m / M. This formula is used to calculate the amount of substance . In reactions 2-3 so had reactants twice more moles than the product because it was necessary to multiply the amount of substance by (2 ) to , know about substance quantities are equal on both sides. The heating of sodium bicarbonate takes place according to reaction # 3 to water, carbon dioxide and sodium carbonate is formed and for amount of substance is the most similar on both sides of the reaction, ie the page before the reaction occurred and the page after the reaction occurred .   

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