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3 years ago

How have ideas about the atom changed in the last two centureies?

1 answer:

dsp733 years ago

8 0

In the past a scientist named dalton produced an atomic theory. There were certain problems regarding his views. So, later on scientists like chadwick, rutherford and thompson added some fresh light for the real identification of the atom.
dalton said the atom was the smallest unit and it CANNOT BE DIVIDED ANY FURTHER.
NOTE... this was renected with the discovery of the proton, neutron and electron as the sub atomic particles.

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2CO + O2 --> 2CO2

GREYUIT [131]

Answer:

10 L of CO₂.

Explanation:

The balanced equation for the reaction is given below:

2CO + O₂ —> 2CO₂

From the balanced equation above,

2 L of CO reacted to produce 2 L of CO₂.

Finally, we shall determine the volume of CO₂ produced by the reaction of 10 L CO. This can be obtained as follow:

From the balanced equation above,

2 L of CO reacted to produce 2 L of CO₂.

Therefore, 10 L of CO will also react to produce 10 L of CO₂.

Thus, 10 L of CO₂ were obtained from the reaction.

3 0

3 years ago

The density of no2 in a 4.50 l tank at 760.0 torr and 25.0 Â°c is ________ g/l.

kap26 [50]

From ideal gas equation that is PV=nRT
n(number of moles)=PV/RT
P=760 torr
V=4.50L
R(gas constant =62.363667torr/l/mol
T=273 +273=298k
n is therefore (760torr x4.50L) /62.36367 torr/L/mol x298k =0.184moles
the molar mass of NO2 is 46 therefore density= 0.184 x 46=8.464g/l

7 0

2 years ago

Read 2 more answers

7. what is the density of an object having a mass of 8.0 g and a volume of 25 cm^3? a) 0.32g/cm^3 b) 2.0 g/cm^3 c) 3.1 g/cm^3 d)

natulia [17]

D = m / V

D = 8.0 g / 25 cm³

D = 0.32 g/cm³

Answer A

6 0

3 years ago

Be sure to answer all parts. Consider the reaction N2(g) + 3H2(g) → 2NH3(g)ΔH o rxn = −92.6 kJ/mol If 4.0 moles of N2 react with

Sphinxa [80]

Answer : The work done is, $1.98\times 10^4J$

Explanation :

The given balanced chemical reaction is:

$N_2(g)+3H_2(g)\rightarrow 2NH_3(g)$

When 4 moles of $N_2$ react with 12 moles of $H_2$ then it gives 8 moles of $NH_3$

First we have to calculate the change in moles of gas.

Moles on reactant side = Moles of $N_2$ + Moles of $H_2$

Moles on reactant side = 4 + 12 = 16 moles

Moles on product side = Moles of $NH_3$

Moles on reactant side = 8 moles

Change in moles of gas = 16 - 8 = 8 moles

Now we have to calculate the change in volume of gas.

Using ideal gas equation:

$PV=nRT$

where,

P = Pressure of gas = 1.0 atm

V = Volume of gas = ?

n = number of moles of gas = 8 mole

R = Gas constant = $0.0821L.atm/mol.K$

T = Temperature of gas = $25^oC=273+25=298K$

Putting values in above equation, we get:

$1.0atm\times V=8mole\times (0.0821L.atm/mol.K)\times 298K$

$V=195.7L$

As the number of moles of gas decreased. So, the volume also deceased. Thus, the volume of gas will be, -195.7 L

Now we have to calculate the work done.

Formula used :

$w=-p\Delta V$

where,

w = work done

p = pressure of the gas = 1.0 atm

$\Delta V$ = change in volume = -195.7 L

Now put all the given values in the above formula, we get:

$w=-p\Delta V$

$w=-(1.0atm)\times (-195.7L)$

$w=195.7L.artm=195.7\times 101.3J=19824.41J=1.98\times 10^4J$

conversion used : (1 L.atm = 101.3 J)

Thus, the work done is, $1.98\times 10^4J$

6 0

3 years ago

A non-stoichiometric compound is a compound that cannot be represented by a small whole-number ratio of atoms, usually because o

ikadub [295]

<span>Average oxidation state = VO1.19
Oxygen is-2. Then 1.19 (-2) = -2.38
Average oxidation state of V is +2.38

Consider 100 formula units of VO1.19
There would be 119 Oxide ions = Each oxide is -2. Total charge = -2(119) = -238
The total charge of all the vanadium ions would be +238.
Let x = number of of V+2
Then 100 – x = number of V+3
X(+2) + 100-x(+3) = +238
2x + 300 – 3x = 238
-x = 238-300 = -62
x = 62

Thus 62/100 are V+2
62/100 * 100 = 62%

</span>62 % is the percentage of the vanadium atoms are in the lower oxidation state. Thank you for posting your question. I hope that this answer helped you. Let me know if you need more help.

7 0

3 years ago