Describe the contributions made by the following scientists to the development of the periodic table.

How would you explain the Earth’s atmosphere?

CaHeK987 [17]

<span>The atmosphere is a thin layer of gases that surrounds the Earth. It seals the planet and protects us from the vacuum of space. It protects us from electromagnetic radiation given off by the Sun and small objects flying through space such as meteoroids.</span><span>

So it's like a blanket protecting us but it has air hole/patches where sunlight can get through</span>

4 0

3 years ago

2000 joules are required to heat 125 grams of an unknown substance from 10 c to 28 c. What is the specific heat of the substance

Delicious77 [7]

Hello! Specific heat is the amount of energy required by known amount of substance to raise its temperature by one degree celsius. In our question it is given that 2000J energy when supplied to 125 g of unknown substance raised its temperature by 18 oC. So, The specific heat is calculated as follow;

3 0

3 years ago

Molly just started a new job. She needs to fill out a _____ so that her employer knows how much tax to take out. 1099 form tax r

xenn [34]

Answer:

The answer is "W-4 form".

Explanation:

The W-4 form is part of the Internal Revenue Service tax form, which is used to submitted by the U.S. government form the customer to information and his or her tax situation. This form informs the customer of the right amount of tax to deduct from his or her salary.

That's why she filled out a W-4 form and know-how often tax he will subtract in the payroll depending on provisions dealing, dependents, potential tax deductions, and credits, etc.

4 0

3 years ago

A 0. 1220 g vitamin c tablet was dissolved in acid. This required 11. 50 ml of 0. 01740 m kio3 to reach the endpoint. Calculate

kodGreya [7K]

86.66 % by weight of ascorbic acid in the tablet, when 0. 1220 g vitamin c tablet was dissolved in acid. This required 11. 50 ml of 0. 01740 m $KIO_3$ to reach the endpoint.

<h3>What is a balanced chemical equation?</h3>

A balanced chemical reaction is an equation that has equal numbers of each type of atom on both sides of the arrow.

$3C_6H_80_6 +3I_2 +KIO_3 +5KI +6H^+$ → $3C_6H_60_6 +6I^- +3I_2+6K^+ +3H_2O$

So, the balanced chemical equation for the reaction will be:

$3C_6H_8O_6 +KIO_3$ → $3C_6H_6O_6 +KI + 3H_2O$

That means, 3 mol of of ascorbic acid reacts with 1 mol of $KIO_3$

Moles of $KIO_3$ available is 0.0174 X 0.0115 =0.0002001 mol

Moles of ascorbic acid to be yielded should be 3 X 0.0002001 =0.0006003

So, percent mass of ascorbic acid in the tablet will be:

(0.1057 / 0.1220) X 100 %

=86.66 %

Hence, the third option is the correct answer.

Learn more about balanced chemical equations here:

brainly.com/question/26750249

#SPJ4

8 0

1 year ago

4. How many grams of ammonium carbonate are needed to decompose in order to produce

Thepotemich [5.8K]

Answer:

14.23g of (NH4)2CO3

Explanation:

We'll begin by writing the balanced equation for the reaction.

(NH4)2CO3 –> (NH4)2O + CO2

Next,, we shall determine the mass of (NH4)2CO3 that decomposed and the mass of CO2 produced from the balanced equation. This is illustrated below:

Molar mass of (NH4)2CO3 = 2[14+(4x1)] + 12 + (16x3)

= 2[14 +4] + 12 + 48

= 2[18] + 60 = 96g/mol

Mass of (NH4)2CO3 from the balanced equation = 1 x 96 = 96g

Molar mass of CO2 = 12 + (2x16) = 44g/mol

Mass of CO2 from the balanced equation = 1 x 44 = 44g.

Summary:

From the balanced equation above,

96g of (NH4)2CO3 decomposed to produce 44g of CO2.

Finally, we can determine the mass of (NH4)2CO3 that decomposed to produce 6.52g of CO2 as follow:

From the balanced equation above,

96g of (NH4)2CO3 decomposed to produce 44g of CO2.

Therefore, Xg of (NH4)2CO3 will decompose to produce 6.52g of CO2 i.e

Xg of (NH4)2CO3 = (96 x 6.52)/44

Xg of (NH4)2CO3 = 14.23g

Therefore, 14.23g of (NH4)2CO3 is needed to produce 6.52g of CO2.

4 0

3 years ago