All categories

3 years ago

How many grams of sucrose will I add to the water (0.100 L) in order to make the 3 molal solution.

Chemistry

1 answer:

Y_Kistochka [10]3 years ago

3 0

Answer:

mass = 102.69 g of sucrose

Explanation:

First, you need to use the correct expression of molality (m) which is the following:

m = moles / kg solvent (1)

According to the exercise, we need to get the grams, in other words, the mass of the sucrose. To get the mass, we need the moles and molecular weight of sucrose and use the following expression:

moles = mass / MM (2)

Now, if we replace (2) in (1) we have:

m = mass / MM * kg solvent (3)

From here, we solve for the mass and then:

mass = m * MM * kg solvent (4)

Now, then density of water is 1 kg/L, so, the volume of the water will be the same as it's mass, and the molality is 3 m. The molecular weight of the sucrose is (according to several sources) 342.3 g/mol. Replacing all the data in (4) we have:

mass = 3 mol/kg * 0.1 kg * 342.3 g/mol

<h2>mass = 102.69 g of sucrose</h2>

Hope this helps

You might be interested in

- Standard state refers to

yulyashka [42]

Answer: The standard state refers to 1 atm and $25^{o}C$ .

Explanation:

It is known that a chemical/substance can either be present in a solid, liquid or gaseous state.

So, when the phase of a substance like solid, liquid or gas is present at 1 atmosphere pressure and at a temperature of $25^{o}C$ then it known as standard state of substance.

Thus, we can conclude that standard state refers to 1 atm and $25^{o}C$ .

4 0

3 years ago

If a molecule can hydrogen bond, does it guarantee that it will have a higher boiling point than a molecule that cannot? Explain

saul85 [17]

Answer:

a): not necessarily due to London Dispersion Forces and dipole-dipole interactions.

b): not necessarily due to London Dispersion Forces.

Explanation:

There are three major types of intermolecular interaction:

Hydrogen bonding between molecules with H-O, H-N, or H-F bonds and molecules with lone pairs.
Dipole-dipole interactions between all molecules.
London dispersion forces between all molecules.

The melting point of a substance is a result of all three forces, combined.

Note that the more electrons in each molecule, the stronger the London Dispersion Force. Generally, that means the more atoms in each molecule, the stronger the London dispersion force. The strength of London dispersion force between large molecules can be surprisingly strong.

For example, $\rm H_2O$ (water) molecules are capable of hydrogen bonding. The melting point of $\rm H_2O$ at $\rm 1\; atm$ is around $0 \; ^{\circ}\rm C$ . That's considerably high when compared to other three-atom molecules.

In comparison, the higher alkane hexadecane ( $\rm C_{16}H_{34}$ , straight-chain) isn't capable of hydrogen bonding. However, under a similar pressure, hexadecane melts at around $18\; ^{\circ}\rm C$ above the melting point of water. The reason is that with such a large number of atoms (and hence electrons) per molecule, the London dispersion force between hexadecane molecules could well be stronger than that the hydrogen bonding between water molecules.

Similarly, the dipole moments in HCl (due to the highly-polar H-Cl bonds) are much stronger than those in hexadecane (due to the C-H bonds.) However, the boiling point of hexadecane under standard conditions is much higher (at around $287\; \rm ^\circ C$ than that of HCl.

3 0

3 years ago

Please help me with these! Mark brainliest

bearhunter [10]

Answer:

1. Alkalinity

2. True

3. Red

Explanation:

1. 8-14, which are the bases, are alkaline

2. Salt lowers the melting/freezing point of water

3. Blue --> Red is Acid

6 0

3 years ago

Which of the following compounds contains the most deactivated aromatic ring.?

sergey [27]

The compound that ontains the most deactivated aromatic ring is the one called Nitrogen dioxide also knwon as NO2. Let me explain a little bit more about the aromatic rings. These rings are simple aromatics, or arenes, that consist of a conjugated planar ring system. Nitrogen generally is a simple aromatic ring that can be heterocyclic because containsnon-carbon ring atoms. The rings of the nitrogen can be separated into basic aromatic rings and that is why this ompound is also refered as a deactivated aromatic ring.

3 0

3 years ago

1. Legătura covalentă este legătura chimică ce se stabileşte: a) prin punere în comun de electroni; b) prin transfer de electron

Inessa [10]

Answer:

1) Option A is correct.

The covalent bond is the chemical bond that is established by pooling of electrons.

2) Option B is correct.

The covalent bond is established between two non-metals.

3) Option B is correct.

A covalent bond is established between nitrogen and hydrogen.

4) Option B is correct.

Covalent bonds are of two types; polar covalent bonds and non-polar covalent bonds.

5) Option B is correct.

Select the substances in the molecules of which the atoms are united by ionic bond.

potassium chloride KCl

1) Opțiunea A este corectă.

Legătura covalentă este legătura chimică care se stabilește prin punerea în comun a electronilor.

2) Opțiunea B este corectă.

Legătura covalentă este stabilită între două nemetale.

3) Opțiunea B este corectă.

Se stabilește o legătură covalentă între azot și hidrogen.

4) Opțiunea B este corectă.

Legăturile covalente sunt de două tipuri; legături covalente polare și legături covalente nepolare.

5) Opțiunea B este corectă.

Selectați substanțele din moleculele cărora atomii sunt uniți prin legătură ionică. clorură de potasiu KCl

Explanation:

English Translation

1) The covalent bond is the chemical bond that is established: a) by pooling electrons; b) by electron transfer; c) by pooling or electron transfer.

2) The covalent bond is established between: a) two metals; b) two non-metals; c) a metal and a non-metal.

3) A covalent bond is established: a) between hydrogen and sodium; b) between nitrogen and hydrogen; c) between aluminum and oxygen.

4) Covalent bonds are of two types: a) single covalent bonds and double covalent bonds; b) polar covalent bonds and non-polar covalent bonds; c) no answer is correct.

5) Select the substances in the molecules of which the atoms are united by ionic bond: a) phosphorus oxide P2O5; b) potassium chloride KCl; c) H2O water

Solution

Covalent bonds are bonds that result from the sharing/pooling of electrons by two non-metallic atoms. When the electronegativity difference between the two atoms in a cobalent bond is substantial, a polar covalent bond results (in which the shared electrons are closer to the more electronegative atom of the pair). If the electronegativity difference isn't significant, a non-polar covalent bond ensues, in which the shared electrons are approximately equidistant from both atoms.

1) The covalent bond is the chemical bond that is established by pooling of electrons.

Already explained above.

2) The covalent bond is established between two non-metals.

Already explained too.

3) A covalent bond is established between nitrogen and hydrogen.

Of the three options, only option B contains two elements, nitrogen and hydrogen, which are both non-metals amd this satisfy the condition for the formation of a covalent bond.

4) Covalent bonds are of two types; polar covalent bonds and non-polar covalent bonds.

Already explained above.

5) Select the substances in the molecules of which the atoms are united by ionic bond.

potassium chloride KCl

Ionic bonds result from the transfer of electrons from metals (electropositive elements) to non-metals (electronegative elements). Of the 3 options provided, only potassium chloride is a coming together of a metal and a non metal.

In Romanian/In limba romana

Legăturile covalente sunt legături care rezultă din împărțirea / îmbinarea electronilor de către doi atomi nemetalici. Când diferența de electronegativitate între cei doi atomi dintr-o legătură cobalentă este substanțială, rezultă o legătură covalentă polară (în care electronii partajați sunt mai apropiați de atomul mai electronegativ al perechii). Dacă diferența de electronegativitate nu este semnificativă, apare o legătură covalentă non-polară, în care electronii partajați sunt aproximativ echidistanți de la ambii atomi.

Legăturile ionice rezultă din transferul electronilor de la metale (elemente electropozitive) la nemetalele (elemente electronegative).

Hope this Helps!!!

Sper că acest lucru vă ajută!!!!

5 0

3 years ago