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3 years ago

How is a compound different from an element 2.3 lesson check?

Chemistry

1 answer:

zavuch27 [327]3 years ago

4 0

Answer:

Element: Element are pure substance consist of same type of atoms
Compound: Form by combination of atoms of different elements.

Distinguish features:

Compounds represented by chemical formula while elements are represented by symbols.
Compounds have fixed ratios of atoms of different elements while in elements are distinguished by atomic no.
Compounds can be converted into simple substance by chemical methods but the elements cant be converted into simpler substance by means of chemical methods.

Example:

Water (H2O) is a compounds.
Iron (Fe) is an element.

Summary:

When two or more elements are mixed then compounds are formed.

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You are provided with a compound fertilizer, 40-15-10.Calculate the quantity of fertilizer to add to a one hectare field supply

victus00 [196]

Answer:

a. 300 kg of Fertilizer

b. 225 kg of fertilizer

c.400 Kg of fertilizer

d.600 Kg of fertilizer

Explanation:

The percentage composition ratio of Nitrogen, Phosphorus and Potassium bag of the given fertilizer is 40:15:10.

The percentages can be expressed as fractions as follows:

For nitrogen; 40/100 = 0.4

For phosphorus; 15/100 = 0.15

For potassium; 10/100 = 0.1

To find the quantity of fertilizer required to add to a hectare to supply the given amount of nutrients, the amount to be provided is divided by the percentage or fractional compostion of each nutrient.

Quantity of fertilizer required to add to a hectare to supply;

a. Nitrogen at 120 kg/ha = 120/0.4 = 300 Kg of fertilizer

b.. Nitrogen at 90 Kg/ha = 90/0.4 = 225 Kg of fertilizer

c. Phosphorus at 60 kg/ha = 60/0.15 = 400 Kg of fertilizer

d. Potassium at 60 kg/ha = 60/0.1 = 600 Kg of fertilizer

5 0

3 years ago

Sodium carbonate (NaCO3) is sometimes used as a water-softening agent. Suppose that a worker prepares a 0.730 M solution of NaCO

elena55 [62]

Answer : The mass of solute in solution is $1.09\times 10^2g$ .

Solution : Given,

Molarity = 0.730 M

Volume of solution = 1.421 L

Molar mass of sodium carbonate = 105.98 g/mole

Formula used for Molarity :

$Molarity=\frac{w}{M\times V}$

where,

w = mass of solute

M = Molar mass of solute

V = volume of solution in liter

Sodium carbonate is solute and water is solvent.

Now put the given values in above formula, we get the mass of solute in solution.

$0.730mole/L=\frac{w}{(105.98g/mole)\times (1.412L)}$

By rearranging the terms, we get

$m=109.247g=1.09\times 10^2g$

Therefore, the mass of solute in solution is $1.09\times 10^2g$ .

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3 years ago

Cite two important quantum-mechanical concepts associated with the Bohr model of the atom.(b) Cite two important additional refi

Alenkinab [10]

Answer: Bohr postulated that electronic energy levels are quantized. Secondly, a photon of light of a particular frequency is emitted when electrons move from a higher to a lower energy levels.

Explanation:

The Bohr model of the atom is the immediate predecessor of the wave mechanical model of the atom. The wave mechanical model refined the Bohr's model by treating the electron as a wave having a wave function psi. The wave function describes the identity of the electron. From Heisenberg uncertainty principle, the position of a particle cannot be accurately and precisely measured. Hence the wave mechanical model added that electrons are not localized in orbits according to Bohr's model but the integral of psi squared dx gives the probability of finding the electron within a given space.

8 0

3 years ago

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Calculate the solubility of benzene in water at 25 c in ppm. the required henry's law constant is 5.6 bar/mol/kg and benzene's s

kap26 [50]

The relationship between pressure and solubility of the gas is given by Henry's law as:

$S_g = kP_g$