All categories

2 years ago

Which scientist proposed the model of an atom as a nucleus surrounded by electrons?

Chemistry

2 answers:

marusya05 [52]2 years ago

8 0

Answer:

The correct answer will be option-Ernest Rutherford.

Explanation:

Atom is the smallest unit of matter which was earlier thought to be indestructible but later new findings suggested that atom contains sub-atomic particles.

The arrangements of these sub-atomic particles in an atom were represented by many models, best accepted of which is presented by Ernest Rutherford in 1911.

His experimental findings concluded that a dense heavy nucleus is present in the center of an atom which is surrounded by a negatively charged nucleus.

Thus, the selected option is the correct answer.

bezimeni [28]2 years ago

3 0

The answer is Ernest Rutherford.

You might be interested in

What is the name of the thermodynamic barrier that must be overcome before products are formed in a spontaneous reaction?

Black_prince [1.1K]

Activation energy is a thermodynamic barrier that must be overcome before products are formed in a reaction. It is the minimum amount of energy needed for a reaction to occur. The energy can be in the form of kinetic or potential energy. This concept was introduced by Svante Arrhenius, which brought about the Arrhenius equation which is a formula used to determine rate of reactions.

3 0

3 years ago

A student has a 2.19 L bottle that contains a mixture of O 2 , N 2 , and CO 2 with a total pressure of 5.57 bar at 298 K . She k

Sergeeva-Olga [200]

Answer: The partial pressure of oxygen gas is 2.76 bar

Explanation:

To calculate the number of moles, we use the equation given by ideal gas which follows:

$PV=nRT$

where,

P = pressure of the gas = 5.57 bar

V = Volume of the gas = 2.19 L

T = Temperature of the gas = 298 K

R = Gas constant = $0.0831\text{ L bar }mol^{-1}K^{-1}$

n = Total number of moles = ?

Putting values in above equation, we get:

$5.57bar\times 2.19L=n\times 0.0831\text{ L. bar }mol^{-1}K^{-1}\times 298K\\\\n=\frac{5.57\times 2.19}{0.0831\times 298}=0.493mol$

To calculate the mole fraction of carbon dioxide, we use the equation given by Raoult's law, which is:

$p_{A}=p_T\times \chi_{A}$ ........(1)

where,

$p_A$ = partial pressure of carbon dioxide = 0.318 bar

$p_T$ = total pressure = 5.57 bar

$\chi_A$ = mole fraction of carbon dioxide = ?

Putting values in above equation, we get:

$0.318bar=5.57bar\times \chi_{CO_2}\\\\\chi_{CO_2}=\frac{0.381}{5.57}=0.0571$

Mole fraction of a substance is given by:

$\chi_A=\frac{n_A}{n_A+n_B}$

We are given:

Moles of nitrogen gas = 0.221 moles

Mole fraction of nitrogen gas, $\chi_{N_2}=\frac{0.221}{0.493}=0.448$

Calculating the partial pressure of oxygen gas by using equation 1, we get:

Mole fraction of oxygen gas = (1 - 0.0571 - 0.448) = 0.4949

Total pressure of the system = 5.57 bar

Putting values in equation 1, we get:

$p_{O_2}=5.57bar\times 0.4949\\\\p_{O_2}=2.76bar$

Hence, the partial pressure of oxygen gas is 2.76 bar

6 0

3 years ago

Explain with example, why there cannot be an oxidation reaction without a corresponding reduction reaction

Vlada [557]

Because matter cannot be created or destroyed

8 0

3 years ago

Read 2 more answers

Rank these compounds by their expected boiling point? CH4 CH3Cl CH3OH? Lowest to highest; 10+ for the best explanation. Thank yo

docker41 [41]

Methane, CH4, would have the lowest boiling point among the three since it has the lowest number of carbon and has no functional groups. Methanol would have the highest boiling point since it has a functional group which contains hydrogen bonding which much stronger than the one in CH3Cl. Hope this helps.

3 0

3 years ago

Read 2 more answers

You have a ballon filled with hydrogen gas which keeps it at a constant pressure, regardless the volume. The initial volume of t

abruzzese [7]

Answer:

619°C

Explanation:

Given data:

Initial volume of gas = 736 mL

Initial temperature = 15.0°C

Final volume of gas = 2.28 L

Final temperature = ?

Solution:

Initial volume of gas = 736 mL (736mL× 1L/1000 mL = 0.736 L)

Initial temperature = 15.0°C (15+273 = 288 K)

The given problem will be solve through the Charles Law.

According to this law, The volume of given amount of a gas is directly proportional to its temperature at constant number of moles and pressure.

Mathematical expression:

V₁/T₁ = V₂/T₂

V₁ = Initial volume

T₁ = Initial temperature

V₂ = Final volume

T₂ = Final temperature

Now we will put the values in formula.

V₁/T₁ = V₂/T₂

T₂ = T₁V₂/V₁

T₂ = 2.28 L × 288 K / 0.736 L

T₂ = 656.6 L.K / 0.736 L

T₂ = 892.2 K

K to °C:

892.2 - 273.15 = 619°C

7 0

2 years ago