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3 years ago

What are the requirements for combustion of a candle?

1 answer:

7 0

For a candle to burn, it requires a spark, which provides the activation energy for the oxidation reaction of the hydrocarbon making the candle.
It also requires oxygen to facilitate the oxidation of the hydrocarbon.
Therefore the two main requirements of combustion of a candle are oxygen and a spark (or an initial flame)

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g Select the statement that best answers the following question What effect does the cation of an ionic compound have on the app

liberstina [14]

Answer:

The cation affects the intensity of the color more than the color of the solution.

Explanation:

According to Beer Lambert law, the intensity of the colour of the solution depends on the concentration of the specie responsible for the colour in the solution.

Let us recall that transition metal compounds are coloured in solution due to electronic transitions.

Therefore, the cation affects the intensity of the color more than the color of the solution.

7 0

3 years ago

Vapor pressure can be described as: A) the temperature at which bubbles of vapor appear in a liquid. B) the pressure exerted on

Vanyuwa [196]

Answer: Option (D) is the correct answer.

Explanation:

Vapor pressure is defined as the pressure exerted by the vapors which are present on the surface of a liquid.

For example, vapor pressure of water at room temperature is 0.0313 atm.

On the other hand, the temperature at which the vapor pressure of a liquid equals atmospheric pressure is known as boiling point.

For example, boiling point of water at room temperature is $100^{o}C$ .

Thus, we can conclude that vapor pressure can be described as the pressure exerted by a gas above the surface of its liquid.

4 0

3 years ago

Sodium metal is sometimes used as a cooling agent in heat exchange units because of its relatively high molar heat capacity of 2

IgorC [24]

Answer:

The specific heat of sodium is 1,23J/g°C

Explanation:

Using the atomic weight of sodium (23g/mol) and the atomic weight definition, we have that each mole of the substance has 23 grams of sodium.

starting from this, we use the atomic weight of sodium to convert the units from J / mol ° C to J / g ° C

$28,2 \frac{J}{mol C} x \frac{1mol}{23g} = 1,23 J/g C$

4 0

3 years ago

Which statement best describes the weather shown by the purple combination of semicircles and triangles on a line on a weather m

BigorU [14]

Answer:

Explanation:

Meteorologists use this symbol to show that the front is a stationary front.

7 0

3 years ago

Read 2 more answers

The NaCl crystal structure consists of alternating Na⁺ and Cl⁻ ions lying next to each other in three dimensions. If the Na⁺ rad

Yuliya22 [10]

Answer : The radii of the two ions Cl⁻ ion and Na⁺ ion is, 181 and 102 pm respectively.

Explanation :

As we are given that the Na⁺ radius is 56.4% of the Cl⁻ radius.

Let us assume that the radius of Cl⁻ be, (x) pm

So, the radius of Na⁺ = $x\times \frac{56.4}{100}=(0.564x)pm$

In the crystal structure of NaCl, 2 Cl⁻ ions present at the corner and 1 Na⁺ ion present at the edge of lattice.

Thus, the edge length is equal to the sum of 2 radius of Cl⁻ ion and 2 radius of Na⁺ ion.

Given:

Distance between Na⁺ nuclei = 566 pm

Thus, the relation will be:

$2\times \text{Radius of }Cl^-+2\times \text{Radius of }Na^+=\text{Distance between }Na^+\text{ nuclei}$

$2\times x+2\times 0.564x=566$

$2x+1.128x=566$

$3.128x=566$

$x=180.9\approx 181pm$

The radius of Cl⁻ ion = (x) pm = 181 pm

The radius of Na⁺ ion = (0.564x) pm = (0.564 × 181) pm =102.084 pm ≈ 102 pm

Thus, the radii of the two ions Cl⁻ ion and Na⁺ ion is, 181 and 102 pm respectively.

4 0

3 years ago