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
Gelneren [198K]
3 years ago
15

what do the colors produced by fireworks indicate? a. a physical change c. a state change b. a chemical change d. an element cha

nge
Chemistry
1 answer:
Nat2105 [25]3 years ago
6 0
B. A chemical change 
You might be interested in
In a test of an automobile engine 1.00 L of octane (702 g) is burned, but only 1.84 kg of carbon dioxide is produced. What is th
Reptile [31]

Answer:

The % yield of CO2 is 85.05 %

Explanation:

Step 1: Data given

Mass of octane = 702 grams

Molar mass octane = 114.23 g/mol

Mass CO2 =1.84 kg = 1840 grams

Molar mass of CO2

Step 2: The balanced equation

2C8H18 + 25O2 → 16CO2 + 18H2O

Step 3: Calculate moles of octane

Moles octane = mass octane / molar mass octane

Moles octane = 702.0 grams / 114.23 g/mol

Moles octane = 6.145 moles

Step 4: Calculate moles of CO2

For 2 moles octane we need 25 moles O2 to produce 16 moles CO2 and 18 moles H2O

For 6.145 moles octane we'll have 8*6.145 moles =49.16 moles

Step 5: Calculate mass of CO2

Mass CO2 = moles CO2 * molar mass CO2

Mass CO2 = 49.16 moles * 44.01 g/mol

Mass CO2 = 2163.5 grams

Step 6: Calculate % yield of carbon dioxide

% yield = (actual yield / theoretical yield)*100%

% yield = (1840/2163.5)*100%

% yield = 85.05 %

The % yield of CO2 is 85.05 %

4 0
3 years ago
A chemist performs the same tests on two homogeneous white crystalline solids, A and B. The results are shown in the table below
Nookie1986 [14]

Solid A contains only Covalent bonds and solid B only contains Ionic bonds. I know this because the appearance, solubility, and conductivity of solid A describes Covalent bonds.

Explanation:

Try this, but idk if it will be marked as correct.

7 0
3 years ago
Write the proper word equation to express the following chemical reaction: 4Fe (s) + 3Sn(NO3)4 (aq) arrow 4Fe(NO3)3 (aq) + 3Sn (
Lapatulllka [165]
The word equation for this reaction is:

Iron + Tin nitrate → Iron nitrate + Tin
3 0
3 years ago
The process of ____ occurs when magma, lava, or a solute in a solution becomes a solid and the internal components will arrange
satela [25.4K]

Answer:

D. Crystallization

Explanation:

Let's clarify the irrelevant terms first.

  1. unification: This term has nothing to do with chemistry at all
  2. lithification: When the problem mentions magma and lava, you might think that this term is related to the process here. However, 'lithification' <em>do </em>have a precise meaning in geology. It refers to the process where sediments collapses into one single rock under pressure, which has nothing to do with the process mentioned here.

Now, for 2 terms that might confuse you: 'solidification' and 'crystallization' these also has precise scientific definition

Solidification is defined the process where substances in <em>liquid</em> phase changes its phase to <em>solid</em>. On first glance, this answer might seems correct, and yes, it is correct for this question. But not the <em>most</em> correct.

The keyword here is  

 'the internal components will arrange its self in an  organized pattern.'

Crystallization is a special case of Solidification where the atoms or molecules of liquid solidify by spontaneously arrange themselves in periodic, ordered, and organized pattern. It might or might not happen during solidification depending on cooling rate, viscosity of liquid, and other factors.

So, Crystallization is the most correct answer here.

4 0
3 years ago
Is a octopus a carnivore or a herbivore
timofeeve [1]
Carnivore, but some are herbivores
4 0
3 years ago
Other questions:
  • In a group assignment, students are required to fill 10 beakers with 0.720 M CaCl2. If the molar mass of CaCl2 is 110.98 g/mol a
    8·2 answers
  • Which would you expect sound to have the greatest speed, 20liter container with 5000 molecules or the 20 liter container with 10
    10·1 answer
  • I need help on this question
    15·1 answer
  • Which level of organization describes the tropical savanna
    15·2 answers
  • Which of these is a characteristic of science?
    9·1 answer
  • If you were allowed to do a science project and it was about the nervous system, why would you do that topic
    12·2 answers
  • What is the resistance of a fluid on an object?
    6·1 answer
  • A sample of O2 gas is put into a bottle at STP. If the volume of the bottle is 0.52 L, how many moles of O2 will the bottle cont
    13·1 answer
  • Which keystone species feed on other animals and prevent them from damaging the ecosystem?.
    13·1 answer
  • Silver nitrate is reacted with magnesium bromide and two products are formed.
    9·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!