What is the practical use of scientific knowledge to solve everyday problems and improve lives?

9- Which pair of formulae represents two alkanes? (1 mark)

Ksenya-84 [330]

Answer:

A) CH4 and C8H18

Explanation:

General Formula for an Alkane = CnH2n+2

This means for every number of Carbon (C) atoms, there are twice as many Hydrogen (H) atoms with an additional two added onto that.

Therefore, if there is one Carbon Atom, and we multiply that by two, and then add an additional two, we get 4 Hydrogen atoms, so CH4, which is our first Formulae

Secondly, if we have eight Carbon Atoms, and we multiple that by two (16), and then add an additional two, we get 18 Hydrogen atoms, so C8H18, which is our second Formulae

The other Formulas do not follow this 'General Formula'

8 0

2 years ago

Calculate the maximum amount of useful work that can be obtained and comment on the spontaneity for the reaction at 25C :

harkovskaia [24]

Answer:

$1.41 *10^{3} kJ/mol$

Explanation:

First, we find in the tables the ΔH of formation of each compound. As you can see in the (image 1)

Then we solve the ecuation for ΔH°reaction

ΔH°reaction=∑ΔH°f(products)−∑ΔH°f(Reactants)

ΔH°reaction= (-2* 393.5 - 2*285.8) - (52.4 + 0) kJ/mol

ΔH°reaction = -1.41 *10^3 kJ/mol

3 0

3 years ago

In 1665 Sir Isaac Newton proposed the fundamental law of gravitation as a universal force of attraction between any two bodies.

natka813 [3]

B. They are the same force. Each body acts on the other. The moon and the earth, and the apple and the earth.

8 0

3 years ago

Read 2 more answers

What mass of NaCl is dissolved in 150 g of water in a .050<br> msolution?

mart [117]

Answer:

0.4383 g

Explanation:

Molality is defined as the moles of the solute present in 1 kg of the solvent.

It is represented by 'm'.

Thus,

$Molality\ (m)=\frac {Moles\ of\ the\ solute}{Mass\ of\ the\ solvent\ (kg)}$

Given that:

Mass of solvent, water = 150 g = 0.15 kg ( 1 g = 0.001 g )

Molality = 0.050 m

So,

$0.050=\frac {Moles\ of\ the\ solute}{0.15}$

$Moles = 0.050\times 0.15\ mol= 0.0075\ mol$

Molar mass of NaCl = 58.44 g/mol

Mass = Moles*Molar mass = $0.0075\times 58.44\ g$ = 0.4383 g

6 0

4 years ago

Use the van der Waals equation and the ideal gas equation to calculate the volume of 1.000 mol of neon at a pressure of 500.0 at

Ugo [173]

Use the van der Waals equation and the ideal gas equation to calculate the volume of 1.000 mol of neon at a pressure of 500.0 atm and a temperature of 355.0 K.

The Van der Waals equation, also known as the Van der Waals equation of state, is an equation of state used in chemistry and thermodynamics that extends the ideal gas law to take into account the effects of molecular interaction as well as the finite size of the molecules in a gas.

We may build a new equation that better reflects real gas behavior by modifying the ideal gas law to include corrections for interparticle attractions and particle volumes. The van der Waals equation can be used to determine a gas's properties under less-than-ideal circumstances.

To learn more about the van der Waals equation please visit
brainly.com/question/13201335
#SPJ4

4 0

2 years ago