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2 years ago

Write the salient features of long form of Periodic Table .

Chemistry

2 answers:

WITCHER [35]2 years ago

5 0

Main Features of the Long Form of the Periodic Table :

(1) It shows arrangement of elements based on modern periodic law.

(2) There are 18 vertical columns known as groups.

(3) There are 7 horizontal rows known as periods.

frez [133]2 years ago

3 0

Answer:

(1) It shows arrangement of elements based on modern periodic law.

(2) There are 18 vertical columns known as groups.

(3) There are 7 horizontal rows known as periods.

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A. As pressure on the gas increases, the volume and temperature will both decrease

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3 years ago

Que diferencia hay entre drogas estimuladoras depresoras y perturbadoras del sistema nervioso

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Answer:

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3 years ago

What is the frequency of this radiation

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3 years ago

Consider the following specific heats: copper, 0.384 J/g· ◦C; lead, 0.159 J/g· ◦C; water, 4.18 J/g· ◦C; glass, 0.502 J/g· ◦C. Wh

Roman55 [17]

Answer:

The correct answer is

2. Water

Explanation:

The specific heat capacity is the amount of heat required to raise the temperature of a unit mass of a substance by one degree. It is connected to the capacity of the substance to retain heat as well as the rate at which it will cool down or heat up when exposed to a specific amount of heat loss or heat supplied. A substance with a low heat capacity such as iron will cool down or heat up more quicker than a substance with a high heat capacity such as water.

From the list of substances water has the highest heat capacity, (4.18 J/g) as such it will retain heat for the longest period of time.

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3 years ago

A compound contains 1.2 g of carbon, 3.2 g of oxygen and 0.2g of hydrogen. Find the formula of the compound

Karolina [17]

Answer:

The empirical formula of the compound is $C_{0.504}HO_{1.008}$ .

Explanation:

We need to determine the empirical formula in its simplest form, where hydrogen ( $H$ ) is scaled up to a mole, since it has the molar mass, and both carbon ( $C$ ) and oxygen ( $O$ ) are also scaled up in the same magnitude. The empirical formula is of the form:

$C_{x}HO_{y}$

Where $x$ , $y$ are the number of moles of the carbon and oxygen, respectively.

The scale factor ( $r$ ), no unit, is calculated by the following formula:

$r = \frac{M_{H}}{m_{H}}$ (1)

Where:

$m_{H}$ - Mass of hydrogen, in grams.

$M_{H}$ - Molar mass of hydrogen, in grams per mole.

If we know that $M_{H} = 1.008\,\frac{g}{mol}$ and $m_{H} = 0.2\,g$ , then the scale factor is:

$r = \frac{1.008}{0.2}$

$r = 5.04$

The molar masses of carbon ( $M_{C}$ ) and oxygen ( $M_{O}$ ) are $12.011\,\frac{g}{mol}$ and $15.999\,\frac{g}{mol}$ , then, the respective numbers of moles are: ( $r = 5.04$ , $m_{C} = 1.2\,g$ , $m_{O} = 3.2\,g$ )