All categories

2 years ago

Why do atomic model has changed over time

1 answer:

8 0

The model of the atom has dramatically changed over many many years.We learned atoms make up different substances and are the smallest particles of matter, which have subatomic particles that are very small portions of matter. At first scientist only thought there were electrons which are negatively charged.

You might be interested in

Draw a correct Lewis structure for XeI2 (Xe in middle, surrounded by I's ) that puts a 0 formal charge on all atoms. How many lo

Alona [7]

1) The Lewis structure will be:

I--I

In this structure, the xenon atom is surrounded by two iodine atoms, which are bonded to it through single bonds. Each iodine atom has one lone pair of electrons, for a total of 2 lone pairs on the central atom (xenon).

2) The molar mass of the gaseous compound is 0.416 g/mol.

To draw a correct Lewis structure for XeI2, we need to first count the number of valence electrons in the molecule. Xenon is a noble gas and has 8 valence electrons, while iodine has 7 valence electrons for a total of 23 valence electrons. To satisfy the octet rule and put a 0 formal charge on all atoms, we can use the following Lewis structure:

I--I

To find the molar mass of the gaseous compound, we can use the ideal gas law:

M = dRT/P

Where M is the molar mass, d is the density, R is the ideal gas constant, T is the temperature, and P is the pressure.

Given that the density of the gas is 0.3876 grams/142 mL = 0.002736 grams/mL, the temperature is 150 + 273 = 423 K, the pressure is 775 torr = 775/760 atm = 1.0132 atm, and the ideal gas constant is 0.08206 L·atm/mol·K.

We can calculate the molar mass as follows:

M = (0.002736 g/mL) * (0.08206 L·atm/mol·K / (1.0132 atm)) * (423 K)

M = 0.416 g/mol

Learn more about molar mass, here brainly.com/question/12127540

#SPJ4

3 0

10 months ago

Antacid tablets commonly contain calcium carbonate and/or magnesium hydroxide. draw the lewis structure for calcium carbonate an

Katyanochek1 [597]

<span>Tums are great antiacid tablets for heartburn and indigestion. Calcium carbonate is a great chemical to treat these conditions. If it were not for calcium carbonate, then many people would have heartburn for years until they eventually died from the condition unfortunately.</span>

7 0

2 years ago

In a be atom a 1s electron has a greater zeff than a 2s electron true or false

Degger [83]

Edrtfyguhiopobhoirhbvw ;iuerjvnwikrjhvn;owjber;ovqjbiufvjbwneri;uqhuoerhjnvhjiurvnwierujvbkqer.jbvliqukjrbvg

7 0

2 years ago

Why is a match being struck a physical change

JulsSmile [24]

Cuz the match can burn and turn in to ash so when it burn and turn in to ash you can't do nothing with the ash hop that make since

3 0

3 years ago

Consider this reaction. What volume of oxygen gas, in milliliters, is required to react with 0.640 g of SO2 gas at S TP? 11.2 mL

DedPeter [7]

Answer:

112mL

Explanation:

We'll begin by calculating the number of mole in 0.640g of SO2.

This is illustrated below:

Molar mass of SO2 = 32 + (16x2) = 64g/mol

Mass of SO2 = 0.640g

Number of mole of SO2 =.?

Mole = mass /molar mass

Number of mole of SO2 = 0.640/64

Number of mole of SO2 = 0.01 mole

Next, we shall determine the number of mole of O2 required for the reaction. This is illustrated below:

2SO2(g) + O2(g) —> 2SO3(g)

From the balanced equation above,

2 moles of SO2 reacted with 1 mole of O2.

Therefore, 0.01 mole of SO2 will react with = (0.01 x 1)/2 = 0.005 mole of O2.

Therefore, 0.005 mole of O2 is required for the reaction.

Finally, we shall determine the volume of O2 required for the reaction as follow:

Note: 1 mole of a gas occupy 22.4L (22400mL) at stp.

1 mole of O2 occupy 22400mL at stp.

Therefore, 0.005 mole of O2 will occupy = 0.005 x 22400 = 112mL

Therefore, 112mL of O2 is required for the reaction.

5 0

2 years ago