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
atroni [7]
3 years ago
8

What are some observable indications that a chemical reaction has occurred?

Chemistry
1 answer:
Leya [2.2K]3 years ago
8 0
Bubbles, release of gas, change in color, release of a smell, change in temperature, formation of a precipitate, 
You might be interested in
When electrons move to a shell closer to the nucleus, energy is released as
Zarrin [17]

Answer:

it is released as lower energy

6 0
2 years ago
Read 2 more answers
What is the surface composition of planets in the solar system?
Over [174]

Answer:

B

Explanation:

Most planets in the solar system don't have water. Helium and hydrogen are two of the many gasses in planets. Therefore, B is the best answer.

4 0
2 years ago
The percent yield of a reaction between elemental zinc and an aqueous solution of 0.50 M hydro-chloric acid is known to be 78.0%
Naddik [55]

Answer:

1.3 × 10³ mL

Explanation:

Let's consider the following reaction.

Zn + 2 HCl → ZnCl₂ + H₂

The percent yield is 78.0%. The real yield (R) of zinc chloride is 35.5 g. The theoretical yield (T) of zinc chloride is:

35.5 g (R) × (100 g T/ 78.0 g R) = 45.5 g T

The molar mass of zinc chloride is 136.29 g/mol. The moles corresponding to 45.5 g of zinc chloride is:

45.5 g × (1 mol/ 136.29 g) = 0.334 mol

The molar ratio of HCl to ZnCl₂ is 2:1. The moles of HCl that react with 0.334 moles of ZnCl₂ are 2 × 0.334 mol = 0.668 mol.

We need 0.668 moles of a 0.50 M HCl solution. The volume required is:

0.668 mol × (1000 mL/0.50 mol) = 1.3 × 10³ mL

3 0
3 years ago
How does deforestation (cutting trees down), affect carbon dioxide levels in the atmosphere?
pickupchik [31]

Answer:

B

Explanation:

Trees have a major impact on the amount of carbon dioxcide, as they take it in in exchange for oxygen. If someone deforested an area, it would lead to higher levels or the gas in the air.

3 0
3 years ago
Read 2 more answers
When of alanine are dissolved in of a certain mystery liquid , the freezing point of the solution is lower than the freezing poi
Kipish [7]

Answer:

The figures and parameters to answer this question are not clearly stated, so I will answer it in the closest best way I can.

Explanation:

Molality of alanine = mole / weight of solvent( kg)

= (170×1000)/(89×600)

= 3.18 molal

We know ∆ T​​​​​​f​​​​​ = K​​​​f × m

K​​​​​​f​​​​​ = ∆ T​​​​f / molality

= 7.9/3.18 = 2.48 °c.kg.mol-1

Now using the value of cryoscopic constant we calculate can't Hoff factor for Ammonium chloride.

i = ∆ T​​​​​​f /( K​​​​f × molality of NH​​​​​4​​​​Cl)

= (24.7 × 53.5 × 600) /(2.48 × 170 × 1000)

= 1.8

4 0
3 years ago
Other questions:
  • What would barium do to obtain a noble gas structure?
    6·2 answers
  • A sample of matter must be copper if(1) each atom in the sample has 29 protons
    5·1 answer
  • 1. ¿Cuál de las siguientes gráficas representa el movimiento rectilineo constante del
    8·1 answer
  • Harry stores toxic chemical waste in a large steel tank that has only 15% of its volume underground. Jena lives in the wildernes
    5·1 answer
  • What drug is the greatest challenge for Forensic Science? What drug in specific is a threat in Forensics.
    10·2 answers
  • How many atoms are there in one molecule of C22H44O?
    7·2 answers
  • Something that can be broken down by living organisms is
    10·1 answer
  • BRAINLIEST IF CORRECT
    14·2 answers
  • Which group of elements gain electrons?
    13·2 answers
  • Convert 675 nanograms to milligrams.
    14·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!