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2 years ago

Which tool should Darla and Rob use to measure the force that pulls a car down the map

Chemistry

1 answer:

svetoff [14.1K]2 years ago

5 0

Answer:

C. A Spring Scale

Explanation:

Using process of elimination, we can quickly decide that a stopwatch and a ruler will not be useful in measuring the force. This leaves us with either the spring scale or a balance scale. A balance scale is used to compare two weights, so this is eliminated. That leaves us with a spring scale. This is because we can attached the spring scale to the car and when we let it go, we can record the force. I hope this helps!

You might be interested in

KNO3(s) --> K+(aq) + NO3-(aq)

ella [17]

Answer:

KNO₃(s) + 35,1 kJ → K⁺(aq) + NO₃⁻(aq)

Explanation:

In the reaction:

KNO₃(s) → K⁺(aq) + NO₃⁻(aq)

The heat absorbed for the reaction (Because the temperature decreases) is:

Q = C×m×ΔT

Where C is specific heat (4,18J/g°C); m is mass (100g); ΔT is (30,0°C-21,6°C = 8,4°C)

Replacing:

Q = 4,18J/g°C×100g×8,4°C

Q = 3511 J

Now, moles of KNO₃ are:

10,1g×(1mol / 101g) = 0,1 moles.

Heat of solution in kJ/mol is:

3,511 J / 0,1 mol = 35,1 kJ

As the heat was absorbed for the reaction, right answer is:

KNO₃(s) + 35,1 kJ → K⁺(aq) + NO₃⁻(aq)

That means the reaction needs the heat to occurs.

I hope it helps!

6 0

3 years ago

The state of matter that has molecules with the least random molecular arrangement:

Ksenya-84 [330]

Gas. Molecules in gas are able to move and vibrate around each other more freely than the molecules in liquids and/or solids due to the great amount of space in between them. Hope this helps! :)

5 0

3 years ago

Upon combustion, a 0.8009 g sample of a compound containing only carbon, hydrogen, and oxygen produces 1.6004 g CO2 and 0.6551 g

Ede4ka [16]

Answer:

C2H4O

Explanation:

We can get the answer through calculations as follows.

From the mass of carbon iv oxide produced, we can get the number of moles of carbon produced. We first divide the mass by the molar mass of carbon iv oxide. The molar mass of carbon iv oxide is 44g/mol

The number of moles of carbon iv oxide is 1.6004/44 = 0.0364

Since there is only one carbon atom in CO2, the number of moles of carbon is same as above

The mass of carbon in the compound is simply the number of moles multiplied by the atomic mass unit. The atomic mass unit of carbon is 12. The mass of carbon in the compound is thus 12 * 0.0364= 0.4368g

From the number of moles of water, we can get the number of moles of hydrogen. To get the number of moles of water, we need to divide the mass of water by its molar mass. Its molar mass is 18g/mol. The number of moles here is thus 0.6551/18 = 0.0364 mole

But there are 2 atoms of hydrogen in 1 mole of water and thus, the number of moles of hydrogen is 2 * 0.0364= 0.0728

The mass of hydrogen is thus 0.0728* 1 = 0.0728g

The mass of oxygen equals the mass of the compound minus that of hydrogen and that of carbon.

= 0.8009 - 0.0728 - 0.4368 = 0.2913 mole

The number of moles of oxygen is the mass of oxygen divided by its atomic mass unit.

That equals 0.2913/16 = 0.0182 mole

The empirical formula can be obtained by dividing the number of moles of each by the smallest which is that of carbon and oxygen 0.0182

H = 0.0728/0.0182 = 4

C= 0.0364/0.0182 = 2

O= 0.0182/0.0182= 1

The empirical formula is thus C2H4O

3 0

3 years ago

The drugs Prilosec and Nexium both contain the same active ingredient. Nexium contains a single enantiomer, but Prilosec is a ra

Softa [21]

Answer:

both drugs will be equally effective

Explanation:

A racemic mixture is a substance that contains a 50/50 mixture of the (+) and (-) enantiomers of an optically active compound.

It is important to note that even if a drug occurs as a racemic mixture, only the biologically active enantiomer will interact with the substrate on which the drug acts. The other enantiomer present is just irrelevant. Similarly, its presence does not affect the biological activity of the active enantiomer.

Hence, both Prilosec and Nexium are both equally effective.

7 0

3 years ago

A scientist measures the standard enthalpy change for the following reaction to be -17.2 kJ : Ca(OH)2(aq) 2 HCl(aq)CaCl2(s)

elixir [45]

Answer: $\Delta H^{0}=-173.72$ kJ/mol

Explanation: Enthalpy Change is the amount of energy in a reaction - absorption or release - at a constant pressure. So, Standard Enthalpy of Formation is how much energy is necessary to form a substance.

The standard enthalpy of formation of HCl is calculated as:

$\Delta ^{0}=\Sigma H_{products}-\Sigma H_{reactants}$