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Answer:

Since all of them are aqueous solutions, the solvent in each solution is H2O. Based on the Raoult's Law, we only have to determine which solution contains the highest mole fraction of the solvent, H2O. The solution that will have the lowest vapor pressure is a. 0.20 m Na2SO4.

Explanation:

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Answer:

moles = 36/180 = 0.2 moles

molarity = 0.2/2 = 0.1 mol/dm3

Considering the reaction stoichiometry, 0.00495 grams of water is produced when  2.75×10⁻⁴ moles of NaOH reacts completely.

Sodium hydroxide (NaOH) and hydrochloric acid (HCl) react to form sodium chloride (NaCl) and water. So, the balanced reaction is:

NaOH + HCl → NaCl + H₂O

By reaction stoichiometry (that is, the relationship between the amount of reagents and products in a chemical reaction), the following amounts of moles of each compound participate in the reaction:

In the periodic table, you can find the molar mass of the elements, also called atomic mass or atomic weight. So, to calculate the molar mass of a compound, you must add the molar mass of the elements of the compound multiplied by the times they appear in the compound.

So, in the case of water:

H₂O= 2× 1 g/mole + 16 g/mole

H₂O= 18 g/mole

Then, if by stoichiometry of the reaction 1 mole of water is produced, the mass of water produced is calculated as:

mass H₂O= 1 mole× 18 g/mole

mass H₂O= 18 g

Then you can apply the following rule of three: if by stoichiometry 1 moles of NaOH produce 18 grams of H₂O, 2.75×10⁻⁴ moles of NaOH will produce how much mass of H₂O?

[tex]mass of H_{2} O=\frac{2.75x10^{-4} moles of NaOHx18 grams of H_{2} O}{1 mole of NaOH}[/tex]

mass of H₂O= 0.00495 grams

In summary, 0.00495 grams of water is produced when  2.75×10⁻⁴ moles of NaOH reacts completely.

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Answer:

I think the answer is Ar, k or just k. Can you pick two answers?

Explanation:

I hope this helps.

P.S. you put two d's

Answer:

the addition of chlorine gas to a solution of potassium iodide.

The reaction that produces a colored substance is the addition of chlorine gas to a solution of potassium iodide. The correct option is D.

In a chemical reaction, reactants undergo a chemical reaction and transform into products through a chemical process. For instance, when humans breathe in oxygen, it combines with glucose to create carbon dioxide, water, and energy.

Another sign that a chemical reaction has taken place is a change in color. If two solutions are combined and a color change occurs that is not just the effect of diluting one of the reactant solutions, a reaction has taken place. A solid and a liquid combined may also result in a change in color.

Therefore, the correct option is D. The addition of chlorine gas to a solution of potassium iodide.

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Answer:

abundance of the first isotope times the Mass of the first isotope

Answer:

1) H - hydrogen - 1.100797

2) HE - helium - 4.00260

3) LI - lithum -6.941

Explanation:

On the periodic table the mass of carbon is reported as 12.01 amu. This is the average atomic mass of carbon. No single carbon atom has a mass of 12.01 amu, but in a handful of C atoms the average mass of the carbon atoms is 12.01 amu.

Answer:

4 = f

3 = d

5 = c

6 = b

2 = a

1 = e

Explanation:

Answer:

3 elements are present in thr compound

Answer: Heat escapes rapidly at night because the air is so dry.

Explanation: The desert has little humidity and rarely is cloudy. These two factors allow the desert to heat up rapidly during the day and cool off quickly at night.

Answer: c

Explanation:

Answer:

C) creating a relationship between mass and volume

g/L

g or gram is mass

L or Litres is for volume

the number of Valence electrons remains the same

Answer:

Higher pitched sounds produce waves which are closer together than for lower pitched sounds. (Think of the slinky - if you produce waves rapidly they will travel quite close to each other, thus demonstrating a higher pitched sound.)

The pitch of a note will depend on a number of factors. One of these is the size of the vibrating object. On a glockenspiel or xylophone the high notes are made by the smaller bars. A smaller triangle or cymbal will make a relatively higher pitch note. On a stringed instrument such as a guitar or violin a thinner string will generally make a higher note, but also shortening the string by stopping it with the finger will produce a similar effect. On a set of pan pipes or a church organ it is the shorter pipes which make the higher notes when the air inside them vibrates.

Another factor which produces higher pitched notes is the tension within the vibrating object. A guitar string can be tuned to a higher pitch by adjusting the string tensioner. An elastic band can be stretched tighter and a drum skin can be tensioned to increase the pitch of the sound it produces.

Answer:

Lustrous

Explanation:

Metals are lustrous which gives them a property of having Shiny surfaces

The valence electrons of metals jump easily to a higher energy orbital when light shines on them then they all fall emitting the excess energy as light show lustrous  property of metals.

Valence electrons are defined as a negatively charged particle that can be shared or transmitted between atoms that is found in the outermost shell of an atom. Valence electrons have a crucial role in determining how an atom will behave. The electrical configurations of elements can be used to find valence electrons. The total number of valence electrons in that element is then determined by counting the number of electrons in the outermost shell.

When newly treated, polished, or broken, a material takes on a bright look and conducts electricity and heat reasonably well. Metals are typically ductile and malleable. These traits are the result of the metallic bond that connects the atoms or molecules of the metal.

Thus, the valence electrons of metals jump easily to a higher energy orbital when light shines on them then they all fall emitting the excess energy as light show lustrous  property of metals.

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Answer:

between metal and nonmetal ions

Explanation:

Answer:

North pole-A

South pole- F

Equator- E

Polar Easterlies-C

Prevailing Westerlies-D or B-not sure

Trade Winds-D or B-not sure

Answer:

look at the explanation

Explanation:

Tides would be much higher also A lunar month would be about 10 days rather than 29 days, so the phases of the moon would go much quicker.

Answer: The answer is D, uneven heating of the Earth by the Sun.

Answer:

The differences in atmospheric pressure generate winds.

Explanation:

At the Equator, the sun warms the water and land more than it does the rest of the world. Warm equatorial air rises higher into the atmospher and migrates towards the poles. The complex relationships between fronts cause different types of winds and weather patterns.

I hope this helps :)

Answer: I do believe it shows variables.

Explanation: