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PtichkaEL [24]
3 years ago
10

Why were gold and copper the first forms of matter investigated by humans

Chemistry
1 answer:
baherus [9]3 years ago
8 0
They were valuable to the eyes of man then.
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What is the percent composition by mass of sulfur in the compound MgSO4 (gram formula mass = 120 g/mol)?
slavikrds [6]

26.7% is the percent composition by mass of sulfur in a compound named magnesium sulfate. Explanation: Molar mass of compound = 120 g/mol.

7 0
2 years ago
The process in which an organic acid and an alcohol react to form an ester and water is known as esterification. Ethyl butanoate
egoroff_w [7]

Answer:

697 g

Explanation:

Ethanol (C₂H₅OH) and butanoic acid (C₃H₇COOH) react to form ethyl butanoate (C₃H₇COOC₂H₅) and water (H₂O).

C₂H₅OH + C₃H₇COOH → C₃H₇COOC₂H₅ + H₂O

The molar ratio of C₂H₅OH to C₃H₇COOC₂H₅ is 1:1. The moles of C₃H₇COOC₂H₅ produced from 6.00 moles of C₂H₅OH are:

6.00 mol C₂H₅OH × (1 mol C₃H₇COOC₂H₅/1 mol C₂H₅OH) = 6.00 mol C₃H₇COOC₂H₅

The molar mass of C₃H₇COOC₂H₅ is 116.16 g/mol. The mass corresponding to 6.00 mol is:

6.00 mol × (116.16 g/mol) = 697 g

7 0
3 years ago
If the decomposition of a sample of k c l o 3 kclox3 produces 3. 29 g of o 2 ox2 , what was the mass (g) of the original sample?
____ [38]

The mass (g) of the original sample after decomposition is 8.3983 g.

A decomposition reaction can be described as a chemical reaction wherein one reactant breaks down into or extra merchandise.

explanation:

Reaction          2KClO₃ ⇒ 2KCl + 3O₂

moles               2               2            3

molar mass    122.55        74.55    32

Given, Mass of O₂ = 3.29g ⇒ moles of O₂

                                            =  (3.29/32) = 0.1028

3 moles of O₂  produced by 2 moles of KClO₃

Therefore, 0.1028 moles of O₂  produced by (2*0.1028/3) = 0.06853 moles of Kclo₃

Mass of KClo₃ in original sample is = moles * molar mass

                                                        = 0.06853 * 122.55

                                                       = 8.3983 g

A decomposition response occurs whilst one reactant breaks down into or extra merchandise. this may be represented through the general equation: XY → X+ Y. Examples of decomposition reactions consist of the breakdown of hydrogen peroxide to water and oxygen, and the breakdown of water to hydrogen and oxygen.

Learn more about decomposition here:-brainly.com/question/27300160

#SPJ4

5 0
1 year ago
For each chemical equation below, write the number of product molecules that will form from the reaction.
Gekata [30.6K]

Answer:

a. 5 moles of CO₂

b. 2 moles of NaCl

c. 3 moles of H₂CO₃

Explanation:

1a. Carbon reacts with oxygen to produce carbon dioxide according to equation below:

C + O₂ ----> CO₂

From the equation of reaction, one mole of carbon reacts with one mole of oxygen to produce one mole of carbon dioxide.

In the given reaction, therefore, 5 moles of carbon will only react with 5 moles of oxygen to produce 5 moles of carbon dioxide. Oxygen is in excess, carbon is the limiting reactant and 5 moles of carbon dioxide are produced. The equation is given below :

5 C + 6 O₂ ---> 5 CO₂

1b. Sodium reacts with chlorine to produce sodium chloride according to the equation below:

2 Na + Cl₂ ---> NaCl

From the equation of reaction, 2 moles of sodium reacts with one mole of chlorine to produce one mole of sodium chloride.

In the given reaction, therefore, 4 moles of sodium will react with only 2 moles of chlorine to produce 2 moles of sodium chloride. Chlorine is in excess, sodium is the limiting reactant and 2 moles of sodium chloride are produced. The equation is given as follows: 4 Na + 8 Cl₂ ---> 2 NaCl

1c. Carbon dioxide reacts with water to produce carbonic acid according to the equation: CO₂ + H₂O ---> H₂CO₃

From the equation of reaction one mole of carbon dioxide reacts with one mole of water to produce one mole of carbonic acid.

In the given reaction, therefore, 3 moles of carbon dioxide will react with only 3 moles of water to produce 3 moles of carbonic acid. Water is in excess, carbon dioxide is the limiting reactant and 3 moles of carbonic acid are produced. The equation is given as follows: 3 CO₂ + 4 H₂O ---> 3 H₂CO₃

4 0
3 years ago
HELP NOW Do Now 3.5 Purple
Serga [27]

Answer:

The smell of a chocolate is from the presence of volatile compounds present in the chocolate bar which at room temperature readily changes phase from solid to liquid to vapor or gas

Explanation:

There are nearly 600 identified compounds present in a chocolate bar and out of these, there are volatile components which gives the chocolate bar its distinctive aroma.

These volatile chocolate contents readily change phase from solid to vapor, with very short duration liquid phase.

For example, 3 methylbutanal, vanillin, and several organic compounds which are known to be readily volatile.

4 0
2 years ago
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