All categories

3 years ago

What are five kinds of evidence you can use to determine if a chemical reaction has occurred?

Chemistry

1 answer:

telo118 [61]3 years ago

5 0

Change of odor, change of color, change of temperature, change of energy, or loss of heat

You might be interested in

What is chemistry? I NEED HELP ASAP!

Thepotemich [5.8K]

the branch of science that deals with the identification of the substances of which matter is composed; the investigation of their properties and the ways in which they interact, combine, and change; and the use of these processes to form new substances.the branch of science that deals with the identification of the substances of which matter is composed; the investigation of their properties and the ways in which they interact, combine, and change; and the use of these processes to form new substances.

3 0

3 years ago

He nucleus contains the cells genetic material in the form of DNA. DNA is organized into our chromosomes, which are made up of t

Sladkaya [172]

Um okay so I'm not 100 percent sure so I asked Google and it said the answer is genes.

5 0

3 years ago

Alum is a compound used in a variety of applications including cosmetics, water purification, and as a food additive. It can be

vlabodo [156]

Answer:

The theoretical yield of alum is 19.873 grams and percent yield for this alum synthesis is 45.33%.

Explanation:

Mass of bottle = 10.221 g

Mass of bottle with aluminium pieces = 11.353 g

Mass of aluminium = 11.353 g - 10.221 g = 1.132 g

Mass of alum and bottle = 19.230 g

Mass of alum = 19.230 g - 10.221 g = 9.009 g

Experimental yield of alum = 9.009 g

Theoretical yield of alum:

$2Al(s) +2 KOH(aq) +4H_2SO_4(aq)+10 H_2O(l) \rightarrow 2 KAl(SO_4)_2.12 H_2O(s)+3H_2(g)$

Moles of aluminium = $\frac{1.132 g}{27 g/mol}=0.041926 mol$

According to reaction, 2 moles of aluminum gives 2 moles of alum.

Then 0.041926 mol aluminium will give :

$\frac{2}{2}\times 0.041926 mol=0.041926 mol$ of alum.

Mass of 0.041926 moles of alum:

0.041926 mol × 474 g/mol= 19.873 g

Theoretical yield of alum = 19.873 g

Percentage yield:

$\% Yield =\frac{\text{Experimental yield}}{\text{Theoretical yield}}\times 100$

Percentage yield of the alum:

$\% Yield =\frac{ 9.009 g}{19.873 g}\times 100=45.33\%$

The theoretical yield of alum is 19.873 grams and percent yield for this alum synthesis is 45.33%.

7 0

4 years ago

Which property of water best explains why ice forms on its surface

lawyer [7]

The hydrogen bonding tendency of water causes it to be 'sticky,' in that water molecules tend to stick together (as in a puddle). This is known ascohesion. Because of this property, water has a high surface tension. This means that it takes a little extra force to break the surface of the water puddle.Mar 13, 2018

5 0

3 years ago

Explain how/why you categorized the substances the way you did. What characteristics of the substances helped you predict whethe

Rasek [7]

The presence of hydrogen and hydroxyl ions determines the acidic and basic nature of a solution.

<h3>What determine acidic and basic nature of a solution?</h3>

The use of the pH scale is one way of determining the acidic and basic nature of solution. If the pH of a solution is less than 7, it is considered as acidic and if the pH is 7, the solution is neutral.

While if the pH is greater than 7,the solution is basic so we can conclude that the presence of hydrogen and hydroxyl ions determines the acidic and basic nature of a solution.

Learn more about substance here: brainly.com/question/2901507

6 0

2 years ago