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3 years ago

9

A book rests on a table. The book pushes downward on the table with a force of 8N. According to Newton's 3rd Law of Motion, what

prevents the book from accelerating downward?

1 answer:

Tems11 [23]3 years ago

7 0

Answer:

The table is preventing the book from accelerating downwards.

Explanation:

You might be interested in

What is the density of heavy water?

vlada-n [284]

<span>1.11 g/cm³

Hope this helps! </span>

6 0

3 years ago

It has been found by mass spectrometric analysis that in nature, the relative abundances of the various isotopic atoms of silico

pochemuha

Answer:

This means that the isotope of silicon with a mass number of 28 is by far the most common of these three isotopes.

Explanation:

The abundance of Si-28 is 92.23%. Si-29 is 4.68% and Si-30 is 3.09%.

Because most Si atoms have a mass of 28 amu, the average mass of all silicon atoms is very close to 28.

Here is a video which summarizes how to calculate average atomic mass from data about mass and relative abundance.

8 0

2 years ago

Which factor can increase the potential energy of an object?

OLEGan [10]

Answer:

Increase in height from the ground.

Explanation:

Potential energy =mass×acceleration due to gravity×height.

P.E= mgh

4 0

2 years ago

For the following reaction, 4.07 grams of aluminum oxide are mixed with excess sulfuric acid. The reaction yields 10.4 grams of

torisob [31]

Answer:

Theoretical yield = 13.7 g

% yield =76 %

Explanation:

For $Al_2O_3$

Mass of $Al_2O_3$ = 4.07 g

Molar mass of $Al_2O_3$ = 101.96 g/mol

The formula for the calculation of moles is shown below:

$moles = \frac{Mass\ taken}{Molar\ mass}$

Thus,

$Moles= \frac{4.07\ g}{101.96\ g/mol}$

$Moles\ of\ Al_2O_3= 0.0399\ mol$

According to the reaction:

$Al_2O_3+3H_2SO_4\rightarrow Al_2(SO_4)_3+3H_2O$

1 mole of $Al_2O_3$ on reaction produces 1 mole of $Al_2(SO_4)_3$

So,

0.0399 mole of $Al_2O_3$ on reaction produces 0.0399 mole of $Al_2(SO_4)_3$

Moles of $Al_2(SO_4)_3$ obtained = 0.0399 mole

Molar mass of $Al_2(SO_4)_3$ = 342.2 g/mol

The formula for the calculation of moles is shown below:

$moles = \frac{Mass\ taken}{Molar\ mass}$

Thus,

$0.0399= \frac{Mass}{342.2\ g/mol}$

$Mass= 13.7\ g$

<u>Theoretical yield = 13.7 g</u>

The expression for the calculation of the percentage yield for a chemical reaction is shown below as:-

$\%\ yield =\frac {Experimental\ yield}{Theoretical\ yield}\times 100$

Given , Values from the question:-

Theoretical yield = 13.7 g

Experimental yield = 10.4 g

Applying the values in the above expression as:-

$\%\ yield =\frac{10.4}{13.7}\times 100$

<u>% yield =76 %</u>

6 0

2 years ago

In preparing your soap, you dissolved 12.5 g of sodium hydroxide in 32.0 mL of de-ionized water. Your product was a solid cake o

Aleksandr [31]

Explanation:

The generated Na+ and OH-ions are immediately surrounded by molecules of water (typically 6, each). There is the development of the exothermic hydration sphere for each ion. It seems as though there is negative overall energy of dissolving solid NaOH.

Now, since this dissolution is exothermic the temperature of the mixture rises.

4 0

2 years ago