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3 years ago

Short note of modern periodic table

1 answer:

5 0

In the modern periodic table, the elements are arranged in the order of their increasing atomic number. In the modern periodic table, there are seven horizontal rows called periods and eighteen vertical columns (1 to 18) called groups. The arrangement of the periods and groups results in formation of boxes.

Explanation:

If it's help pls give me Brainliest!!

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Describe the three temperature scales used in the laboratory and in everyday life: the Fahrenheit, Celsius, and Kelvin scales.

yuradex [85]

Explanation:

Fahrenheit Scale

Fahrenheit temperature scale is the scale which is based on:

(a) For freezing point of the water, 32 °F.

(b) For boiling point of the water, 212 °F.

With interval between two being divided into equal 180 parts.

Celsius Scale

Celsius temperature scale is the scale which is based on:

(a) For freezing point of the water, 0 °C

(b) For boiling point of the water, 100 °C.

With interval between two being divided into equal 100 parts.

Kelvin Scale 

It denotes the triple point of water where the solid, liquid, and gas phases exist in equilibrium which is at 273.16 K.

kelvin is defined as 1/ 273.16 of triple point temperature.

6 0

3 years ago

How many grams of a 22.9% sugar solution contain 68.5 g of sugar?

777dan777 [17]

The grams of 22.9 % sugar solution that contain 68.5 g of sugar is 299.13 g of solution

calculation

22.9% means that there are 22.9 g of sugar in 100 g of solution.

what about 68.5 g of sugar

- by cross multiplication

=[(68.5 g sugar x 100 g solution) /22.9 g sugar] =299.13 g of solution

Nb; g sugar cancel each other

5 0

3 years ago

Which would be the best to neutralize a large acid spill in your school lab: sodium hydroxide or baking soda? Explain.

nadya68 [22]

Consider the acid spill. It is already starting to do nasty things to, say, the floor or counter. So you grab the bottle of 10% NaOH and pour some on the spill. All of a sudden, you get a great deal of heat, and you don't have any visual evidence whether your put on too little or too much. But you have added more liquid to the spill, generated more heat, and will get more damage. You have made a bigger mess, and if you added too much, you then have a neutralization problem to deal with.

And if it is something like a strong sulfuric acid solution, adding sodium hydroxide solution will be extremely exothermic, and you could get some really nasty results.

So now approach the spill with a handful of baking soda. You sprinkle it on the spill. It fizzes, and carbon dioxide is given off. That actually, in a very tiny way, moderates the temperature of the neutralization. And you can keep adding baking soda until the fizzing stops, and then perhaps some water to mix everything well. But what you have done is kept the volume to a minimum, added a neutralization agent that has a visible endpoint (no more gas being given off), and you don't suddenly have a huge amount of highly basic solution because you added too much.

And what is also nice about baking soda is that you can toss some with your hand or even with a spoon, and get some distance from the spill. With a liquid, you have to get much closer

i hope this helped..

5 0

3 years ago

I need help with 4, 5, 8, 9, and 6. Quickly I need it before class starts. Worth points!!!!!! HelP

GalinKa [24]

Answer:

4. 264.6J

5. 37.5J

6. 96J

7. 55Watts

8. 77.14m

9. 6s

10. 750Watts

Explanation:

4). Mechanical energy (potential energy) = mass (m) × acceleration due to gravity (g) × height (h)

m = 3kg, h = 9m, g = 9.8m/s²

P.E = 3 × 9 × 9.8

= 264.6J

5). Kinetic energy (K.E) = 1/2 × m × v²

Where;

m = mass (kg) = 3kg

v = velocity (m/s) = 5m/s

K.E = 1/2 × 3 × 5²

K.E = 1/2 × 3 × 25

K.E = 1/2 × 75

K.E = 37.5J

6). Work done (J) = Force (N) × distance (m)

Force = 12N, distance = 8m

Work done = 12 × 8

= 96J

7). Power = work done (J) ÷ time (s)

Work done = 550J, time = 10s

Power = 550/10

= 55Watts.

8). Work done = force (F) × distance (m)

Work done = 540J, force = 7N, distance = ?

540 = 7 × d

540 = 7d

d = 540/7

d = 77.14m

9). Power = work done (J) ÷ time (s)

Work done = 300J, time = ?, Power = 50Watts.

50 = 300/t

50t = 300

t = 300/50

t = 6seconds.

10). Power = work done (J) ÷ time (s)

This means that;

Power = force × distance / time

Force = 300N, distance = 5m, time = 2s

Power = 300 × 5 ÷ 2

Power = 1500 ÷ 2

Power = 750Watts

3 0

3 years ago

Compared to winds on the earth the winds on Saturn are much stronger. True or False?

Yanka [14]

This is most definitly true

3 0

3 years ago