1answer.
Ask question
Login Signup
Ask question
All categories
  • English
  • Mathematics
  • Social Studies
  • Business
  • History
  • Health
  • Geography
  • Biology
  • Physics
  • Chemistry
  • Computers and Technology
  • Arts
  • World Languages
  • Spanish
  • French
  • German
  • Advanced Placement (AP)
  • SAT
  • Medicine
  • Law
  • Engineering
Ostrovityanka [42]
3 years ago
5

List 4 factors that suggest a chemical reaction has taken place

Chemistry
1 answer:
Degger [83]3 years ago
3 0
The change in smell, The change in taste, If there is rust, i cant think of any other on the spot but if something were to catch fire then there is a chemical change.
You might be interested in
In order to design an experiment, you need a ____ about the scientific question you are trying to answer. A. decision B. procedu
kolbaska11 [484]

The correct answer is option C, that is, hypothesis.  

The hypothesis is the starting building block in the scientific method. It is also illustrated as an educated guess, based on previous observation and knowledge. A hypothesis refers to a recommended solution for an unexplained event, which does not fit into the present accepted scientific theory.  

The fundamental concept of a hypothesis is that there is no pre-determined result. For a hypothesis to be considered as scientific hypothesis, it has to be something, which can be refuted or supported via carefully crafted observation or experimentation.  


4 0
2 years ago
Which phase change results with increased kinetic energy?
weqwewe [10]

An increase in kinetic energy corresponds to an increase in temperature. Out of boiling, condensation, freezing, and precipitation, boiling is the only one that indicates an increase in temperature.

3 0
3 years ago
How many grams of h2 are needed to produce 10.78 g of nh3?
balu736 [363]
Ammonia is formed by a reaction between hydrogen and nitrogen as shown by the equation below.
N2(g) + 3H2(g) = 2NH3(g)
1 mole of ammonia contains 17 g
Therefore 10.78 g of ammonia are equivalent to 10.78/17 = 0.6341 moles
The mole ratio of hydrogen to ammonia is 3 : 2
Therefore, moles of hydrogen used will be  0.6341 × 3/2 = 0.9512 moles
1 mole of hydrogen is equivalent to 2 g
Thus, the mas of hydrogen will be 0.9512 moles × 2 = 1.9023 g
6 0
3 years ago
Oil doesn't mix with water because
puteri [66]
<span>Oil and water don't mix because oil is made up of non-polar molecules while water molecules are polar in nature. Because water molecules are electrically charged, they get attracted to otherwater molecules and exclude the oil molecules. (this is from wiki)</span>
5 0
2 years ago
the red line observed in the line spectrum for hydrogen has 3.03x10^-19J, what is the wavelength, in nm, of this?
djverab [1.8K]

Answer:

λ = 6.5604 x 1016 nm

Explanation:

Given Data:

The energy of the red line in Hydrogen Spectra = 3.03 x 10-19

Formula to calculate Wave length

E= hv

Where E is Energy

h is Planks Constant = 6.626 x 10–34 J s

v is frequency

In turn

v= c/ λ

where c is speed of light = 3.00 x 108 m s–1

λ is wavelength = to find

Solution:

Formula to be Used:

E= hv………………………… (1)

Putting the value v in equation 1

               E= h c/ λ…………………… (2)

Put the value in equation 2

3.03 x 10-19 J  = (6.626 x 10–34 J s) x (3.00 x 108 m s–1) / λ ……………………….(3)

By rearranging equation 3

λ = (6.626 x 10–34 J s) x (3.00 x 108 m s–1) /3.03 x 10-19  J

λ = 6.5604 x 107 m

The answer is in “m”

So we have to convert it into nm

So for this to convert “m” to “nm” multiply the answer with 109

λ = 6.5604 x 107 x 109

λ = 6.5604 x 1016 nm

6 0
3 years ago
Other questions:
  • What is a unicellular organism?
    10·2 answers
  • The U.S. quarter has a mass of 5.67 g and is approximately 1.55 mm thick.
    7·1 answer
  • Which structure is responsible for breaking down sugar molecules in order to supply energy to the cell?
    13·1 answer
  • Una solución formada por 58 gramos de cloruro de sodio (NaCl) en 100 mL de solución posee una concentración
    8·1 answer
  • 20 POINTS PLEASE ANSWER
    6·1 answer
  • Not related to any subject but how do you tell someone you like them?
    8·1 answer
  • What is the freezing point (in degrees Celcius) of 3.75 kg of water if it contains 189.9 g of C a B r 2?
    6·2 answers
  • Do you think that it is possible for that viruses can grow and respond to changes in their environment? Why or why not?
    9·2 answers
  • Please help-- 15 pts!
    9·2 answers
  • Which of the following is the only genotype not able to taste PTC.<br> a. IT<br> b. Tt<br> c. tt
    15·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!