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
Leni [432]
3 years ago
9

A student is investigating the affect of different salts on melting points. Four patches of ice of equal size are roped off and

a different type of salt is poured on each, one receives table salt (NaCl), one receives Calcium Chloride (CaCl2), one receives Potassium Carbonate (KCO3) and the fourth receives inert sand instead. Each patch receives an equal amount of salt or sand. The student measures the volume of ice remaining and subtracts it from the original volume of ice to see how much melted away. What is a control variable in this experiment?
Chemistry
2 answers:
eduard3 years ago
8 0

Answer: Fourth one which received inert sand.

Explanation:

A control variable is the one which remains unchanged in an experiment. It does not receive any treatment. It is considered as a benchmark or standard for comparison of changes occurring in the dependent or experimental variable.

According to the given situation, the fourth one is the correct option as the inert sand will not have any effect over the melting of ice. This can be useful for comparison of the effect of salts on the ice.

stealth61 [152]3 years ago
6 0

Answer:

The inert sand

Explanation:

A control variable is the variable in which the experiment does not depend on. The outcome of the control variable does not in any way validate or invalidate an experimental procedure.

The student seeks to investigate the effect of different salts on melting point. He used NaCl, CaCl₂, K₂CO₃ and inert sand. The first three are salts. Sand is made up of silica, SiO₂ and it is not a salt. Therefore, the control variable here is the inert sand. Sand is highly unreactive and would not in any significant way help the investigation.

You might be interested in
Complete the following statements about the functions of the digestive system. The starts an involuntary swallowing action when
Eduardwww [97]

Answer:

pharynx esophagus peristalsis chyme

Explanation:

5 0
3 years ago
Sometimes voltage is also called A. electrical force. B. electrical potential. C. electrical resistance. D. electrical field ene
Oliga [24]
Voltage<span>, </span>also called<span> electromotive force, is a quantitative expression of the potential difference in charge between two points in an electrical field.

So ACTUALLY an "electromotive force", but of your answer choices.

D. Electrical Field Energy
</span>
7 0
3 years ago
Read 2 more answers
How did the work of Dmitri Mendeleev differ from that of John Newlands in the development of the periodic table?
alex41 [277]
When Newlands tried to create a periodic table, his tried to conform to the "Rule of Octaves" he had discovered. He had the right idea, in that if you arrange the elements by atomic weight there would be similarities every 7 elements (not 8 because noble gases hadn't been discovered yet) but he tried to push this rule so much that he would put multiple elements in the same box to try to keep the rule. Mendeleev, however, left gaps in this table for undiscovered elements, which paved the way for our modern periodic table.
3 0
3 years ago
Which statements are inconsistent with dalton's atomic theory as it was originally stated?
Blababa [14]

Missing question:

A. All carbon atoms are identical.

B. An oxygen atom combines with 1.5 hydrogen atoms to form a water molecule.

C. Two oxygen atoms combine with a carbon atom to form a carbon dioxide molecule.

D. The formation of a compound often involves the destruction of one or more atoms.

Answer is: B and D.

A is correct because Daltan stated: All atoms of a given element have the same mass and other properties that distinguish them from the atoms of other elements.

C is correct because atoms combine in simple, whole- number ratios to form compounds, B is incorrect because ratio is not simple, whole number.

D is incorrect because according to Dalton. atoms can't be created or destroyed.

3 0
3 years ago
Choose the most electronegative atom from the following: K, Mg, As, CI
lyudmila [28]

Answer:

Cl

Explanation:

Electronegativity increases as you move up and to the right of the periodic table. For example, Florine is the most electronegative element.

8 0
2 years ago
Other questions:
  • Which of the following is the correctly balanced chemical equation for the reaction Ca(OH)2 and HNO3
    10·2 answers
  • What is the chemical formula for sodium sulfate?
    9·1 answer
  • The __________ would be of the most benefit when transporting goods from Spain to Italy.
    13·1 answer
  • Quick question
    7·1 answer
  • In the following reaction the iodide ion (I-) in HI is oxidized by the permanganate ion (MnO4-). A 5.0 mL solution of 0.20M HI r
    8·1 answer
  • The graph above plots gravitational force versus distance for two asteroids of equal mass (10 billion kg). When the distance bet
    6·2 answers
  • 6. Calculate the mass of each product when 100.0 g of CuCl react according to the reaction
    5·1 answer
  • if 8.15 ml of water is placed in a graduated cylinder the mass of the cylinder = 56.98g and the combined mass of both the cylind
    14·1 answer
  • Why has the acidity of the ocean increased over the years?
    12·1 answer
  • What is a substrate?
    11·1 answer
Add answer
Login
Not registered? Fast signup
Signup
Login Signup
Ask question!