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4 years ago

What does the root word for "atom" mean and why is that not an accurate name?

Chemistry

1 answer:

aev [14]4 years ago

7 0

Explanation:

The word atom is coined from ancient greek word atomos and it means uncuttable.

Democritus coined the word and he believed that an atom is the smallest indivisible particle of any matter.

He suggested that all matter is made up of atom and atoms cannot be broken down into smaller pieces.

This is not accurate today because we know that atoms contains very small particle of proton, neutrons and electrons.

Atoms are divisible and can be changed another by nuclear reaction.

learn more:

Dalton model of the atom brainly.com/question/1979129

#learnwithBrainly

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Classify lead: Select one: C = compound HE = heterogeneous mixture S = homogeneous mixture/solution E = element

Ira Lisetskai [31]

Lead is an E (element) and can be found on the periodic table.

5 0

3 years ago

If 50.0 g of KCl reacts with 50.0 g of O2 to produce KClO3 according to the following equation, how many grams of KClO3 will be

Sliva [168]

Answer:

A. 82.2g of KClO3

B. Word equation:

50g of KCl react with 50g of O2 to produce 82.2g of KClO3

C. Formula equation:

2KCl + 3O2 —> 2KClO3

Explanation:

The balanced equation for the reaction. This is given below:

2KCl + 3O2 —> 2KClO3

Next, we shall determine the masses of KCl and O2 that reacted and the mass of KClO3 produced from the balanced equation. This is illustrated below:

Molar Mass of KCl = 39 + 35.5 = 74.5g/mol

Mass of KCl from the balanced equation = 2 x 74.5 = 149g

Molar Mass of O2 = 16x2 = 32g/mol

Mass of O2 from the balanced equation = 3 x 32 = 96g

Molar Mass of KClO3 = 39 + 35.5 + (16x3) = 122.5g/mol

Mass of KClO3 from the balanced equation = 2 x 122.5 = 245g

Summary:

From the balanced equation above:

149g of KCl reacted.

96g of O2 reacted.

245g of KCl were produced.

Next, we shall determine the limiting reactant. This is illustrated below:

From the balanced equation above,

149g of KCl reacted with 96g of O2.

Therefore, 50g of KCl will react with = (50 x 96)/149 = 32.21g of O2.

Since a lesser mass of O2 ( i.e 32.21g) than what was given (i.e 50g) is needed to react completely with 50g of KCl, therefore, KCl is the limiting reactant and O2 is the excess reactant.

A. Determination of the mass of KClO3 produced from the reaction.

In this case the limiting reactant will be used.

From the balanced equation above,

149g of KCl reacted To produce 245g of KClO3.

Therefore, 50g of KCl will react to produce = (50 x 245)/149 = 82.2g of KClO3.

Therefore, 82.2g of KClO3 is produced from the reaction.

B. Word equation:

50g of KCl react with 50g of O2 to produce 82.2g of KClO3.

C. Formula equation:

2KCl + 3O2 —> 2KClO3

4 0

4 years ago

A can was filled with crushed ice, sealed, and massed. The ice was melted by slowly warming the can and its contents. No water v

Lera25 [3.4K]

Answer:

A) The mass would be the same.

Explanation:

Since there is no loss of any particle to vapor during the phase change process from solid to liquid, the mass of the before and after the process will remain the same.

In this way, the law of conservation of mass is obeyed.
Mass is the amount of matter contained in a substance.
Since there is no room for escape or matter loss, the mass will remain the same.

8 0

3 years ago

Read 2 more answers

How is the mass in grams of the element converted to amount in atoms

Alik [6]

A substance's molar mass is calculated by multiplying its relative atomic mass by the molar mass constant (1 g/mol). ... By multiplying a given mass by the molar mass, the amount of moles of the substance can be calculated.

8 0

3 years ago

A student mixed 50 ml of 1.0 M HCl and 50 ml of 1.0 M NaOH in a coffee cup calorimeter and calculated the molar enthalpy change

MrRa [10]

Answer:

-54 kJ/mol

Explanation:

Given that:

A student mixed 50 ml of 1.0 M HCl and 50 ml of 1.0 M NaOH in a coffee cup calorimeter and calculated the molar enthalpy change of the acid-base neutralization reaction to be –54 kJ/mol

i.e

50 ml of 1.0 M HCl + 50 ml of 1.0 M NaOH -----> -54 kJ/mol

If he repeat the same experiment with :

100 ml of 1.0 M HCl + 100 ml of 1.0 M NaOH. ------> ????

From The experiment; the molar enthalpy of change of the acid-base neutralization reaction will be -54 kJ/mol

This is because : The second reaction requires 50 ml in order to neutralize the reaction, then the remaining 50 ml will be excess, Hence, there is no change in the enthalpy of the reaction.

Similarly; we can assume that :

In the first reaction; P moles of is used to liberate Q kJ heat ; then the change in molar enthalpy will be Q/P (kJ/mol).

SO; when he used 100 ml ;

then the amount of moles used is double, likewise the heat liberated will be doubled ;

So;

2P moles is used to liberate 2Q kJ heat ;

2P/2Q = Q/P ( kJ/mol) = -54 kJ/mol

8 0

3 years ago