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
Lana71 [14]
3 years ago
11

Ben and Jerry were testing powders in science lab. First they put the powder in a zip lock bag. Next they added some water. The

powder fizzed and bubbled; soon it disappeared. When the bubbling stopped the bag contained a clear liquid and a lot of gas. What is the MOST OBVIOUS sign of a chemical change in this reaction. A) A gas was produced. B) The powder mixed with the water. C) There was a change in temperature. D) The powder dissolved in the water.
Chemistry
2 answers:
tangare [24]3 years ago
8 0
A) because when gas is produced it changes chemical form whereas the chemical change is obvious.
Montano1993 [528]3 years ago
5 0

Answer:

A) A gas was produced.

Explanation:

In a chemical change there is always a change in the chemical composition. When reactant reacts with one another new products are formed, the products have a different chemical composition than the reactants.  Option A is correct as gases have evolved as a result of chemical change.

Option B and D are physical changes therefore incorrect. When matter dissolves in water or mixes with another substance there is no change in the chemical composition of the said matter.

Option C is incorrect as change in temperature is a change in the kinetic energy of matter and is not a chemical change.

You might be interested in
Which is a characteristic of a mixture?
Fudgin [204]

Answer:

A mixture is the blending of two or more dissimilar substances. A major characteristic of mixtures is that the materials do not chemically combine. Mixtures can be divided into those that are evenly distributed (homogeneous) and those that aren't (heterogeneous).

Explanation:

3 0
3 years ago
A 2.00 liter evacuated container has a mass of 1050.0 g. When the container is filled with an unknown gas at 800. mm Hg pressure
Andrei [34K]

Answer:

(A) 28

Explanation:

To solve this problem we use the <em>PV=nRT equation</em>, where:

  • P = 800 mmHg ⇒ 800/760 = 1.05 atm
  • V = 2.00 L
  • n = ?
  • R = 0.082 atm·L·mol⁻¹·K⁻¹
  • T = 25.0 °C ⇒ 25.0 + 273.16 = 298.16 K

We<u> input the data</u>:

  • 1.05 atm * 2.00 L = n * 0.082 atm·L·mol⁻¹·K⁻¹ * 298.16 K

And <u>solve for n</u>:

  • n = 0.086 mol

Now we calculate the gas' mass:

  • Gas Mass = (Mass of Container w/ Gas) - (Mass of Empty Container)
  • Gas Mass = 1052.4 g - 1050.0 g = 2.4 g

Finally we <u>calculate the unknown gas' molar mas</u>s, using<em> its mass and its number of moles</em>:

  • Molar Mass = mass / moles
  • Molar Mass = 2.4 g / 0.086 mol = 27.9 g/mol

So the answer is option (A).

5 0
3 years ago
Calculate the mass in grams of 1.72×10^24 molecules of formaldehyde. The chemical formula for formaldehyde is CH2O.
pishuonlain [190]

Answer: m= 85.8 g CH2O

Explanation: First step is convert the molecules of CH2O to moles using the Avogadro's Number.

1.72x10²⁴ molecules CH2O x 1 mole CH2O / 6.022x10²³ molecules CH2O

= 2.86 moles CH2O

Next is convert the moles of CH2O to mass using the molar mass of CH2O

2.86 moles CH2O x 30 g CH2O / 1 mole CH2O

= 85.8 g CH2O

5 0
3 years ago
What is the chemical name of the compound Na2CO3? Use the list of polyatomic ions and the periodic table to help you answer.
m_a_m_a [10]

Answer:

I believe the answer is B. Sodium carbonate

5 0
3 years ago
Read 2 more answers
During photosynthesis, plants transform
attashe74 [19]
During Photosynthesis , Plants Transforms Light Energy Into Chemical Energy .
6 0
3 years ago
Other questions:
  • What controls which substances can move into and out of a cell?
    15·1 answer
  • Why do automobiles rust more easily in wet climate than drier climates
    11·1 answer
  • What is the half-life of a radioisotope if 25.0 grams of an original 200.-gram sample of the isotope remains unchanged after 11.
    7·2 answers
  • A gas effuses 4.0 times faster than oxygen (O2). What is the molecular mass of the gas?
    14·1 answer
  • Which electrons in a calcium atom in the ground state have the greatest effect on the chemical properties of calcium
    6·2 answers
  • Consider the reaction: A(aq) + 2B (aq) === C (aq). Initially 1.00 mol A and 1.80 mol B
    12·1 answer
  • HELP PLEASE!!!!!!!
    6·1 answer
  • What is the H concentration in a solution with a pH of 1. 25? Round to the nearest hundredth. × 10n M n=.
    7·1 answer
  • It requires 2,500 joules to raise a certain amount of water (c = 4.186 j/g°c) from 20.0°c to 60.0°c. what is the mass of the wat
    8·1 answer
  • Given the reaction below, if 0.003 g of carbon dioxide is used up, how many grams of oxygen will be produced? (show work)
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!