How many polyatomic ions (s) below contain a total of four atoms?

8. When a 2.5 mol of sugar (C12H22O11) are added to a certain amount of water the boiling point is raised by 1 Celsius degree. I

Tamiku [17]

Answer:

The boiling point of the water by adding 2.5 moles of aluminium nitrate will be changed by 4° C.

Explanation:

Step 1: define the formula for an elevation of the boiling point

Δ T b = i *K b *bB

⇒with Δ T b = the elevation of the boiling point ( in °C or Kelvin)

⇒with i = van't Hoff i -factor for the solute. The factor i shows the number of individual particles (typically ions) that are formed by a compound in the solution.

⇒ with Kb = ebullioscopic constant, which depends on the properties of the solvent. (Eventually can be calculated).

⇒ with bB= the molal concentration (molality) of the solute.

Since we have 2 different solutions ( component 1 = sugar and component 2 = aluminium nitrate) of the same molality in the same solvent ( water). We can express this as followed:

Δ T b,2 / Δ T b,1 = (i2 * Kb * bB ) / (i1 * Kb *bB)

⇒after he was simplifying this becomes:

Δ T b,2 / Δ T b,1 = i2 / i1

⇒ Now we can isolate either Δ T b,2 or Δ T b,1:

Δ T b,2 =(i2/i1) x Δ T b,1

Sugar

⇒ is a covalent compound, so it doesn't dissociate in water ⇔ i1=1

Aluminium nitrate

⇒ it's a soluble ionic compound and in solution it will dissociate as the following equation:

Al(NO3)3 (aq) → Al3+(aq) + 3NO3- (aq)

⇒thus here are 4 particels formed : 1 Al3+ + 3NO3-

i2=4

As given, we also know that the temperature was raised by 1°C after adding sugar ⇒ Δ T b,1 = 1°C

Step 2: insert all the numbers in the formula for boiling point elevation

(i2/i1) x Δ T b,1

(4/1 ) x 1°C = 4°C

⇒ The boiling point of the water by adding 2.5 moles of aluminium nitrate will be changed by 4°C

6 0

3 years ago

The table below lists the properties of a metallic element. (Shiny, silver colored, forms +1 and +2 ions, and compound with sulf

Triss [41]

Answer:

Group 13

Explanation:

We have been given some properties of the elements we desire to identify.

The most important and by far unique is the oxidation state of the ions given. This reflects the amount of electrons an atom has lost or gained.

Group 1 and 2 elements have oxidation states of +1 and +2 respectively. This is a very perculiar property of these metals. When group 1 elements lose an electron, nobility is achieved and this goes for group 2 elements too.

Group 12 consists of transition elements. Most transition elements are known to have variable oxidation states. In this group, the common oxidation state is +2.

Group 13 elements have two dominant oxidation numbers which are +1 and +3. Particularly, Aluminum has +2 oxidation state too.

The properties fits in well for aluminum which is a group 13 element.

4 0

4 years ago

Read 2 more answers

What is the role of meteorites in the formation of life?

CaHeK987 [17]

Answer:

Meteorites are consensually considered to be involved in the origin of life on this Planet for several functions and at different levels: (i) as providers of impact energy during their passage through the atmosphere; (ii) as agents of geodynamics, intended both as starters of the Earth’s tectonics and as activators of local hydrothermal systems upon their fall; (iii) as sources of organic materials, at varying levels of limited complexity; and (iv) as catalysts.

Explanation:

4 0

3 years ago

Please help in Chemistry!!!! 15 points! I added a picture below...

krek1111 [17]

The answer would be choice B because the energy decreased by 20 J

5 0

3 years ago

Read 2 more answers

What is the mole fraction of each component in a solution made by mixing 300 g of ethanol(C2H5OH) and 500 g of water?

Snowcat [4.5K]

Answer:

The mole fraction of ethanol and water in the solution are 0.19 and 0.81 respectively.

Explanation:

The Molar Fraction is a way of measuring the concentration that expresses the proportion in which a substance is found with respect to the total moles of the solution, which are calculated by adding the moles of solute (s) and solvent.

It is calculated by dividing the number of moles of one of the components by the total number of moles of the solution.

The sum of all the molar fractions of the substances present in a solution is equal to 1.

So, the expression to calculate the mole fraction is:

$Molar fraction (Xi)=\frac{moles of sudstance}{total moles of the solution}$