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3 years ago

Please answer he questions

Chemistry

1 answer:

Nastasia [14]3 years ago

6 0

"Work done by a constant force on an object is the product of the force and the distance moved by the object in the direction of the force" -textbook

There is work done ONLY if the direction of the force and the direction the item is moving are the same. In figure A, the direction of the force (the lifting) is upwards (defying gravity), and the book is moving upwards, so work is done. In figure B, the force is still moving upwards (the person is carrying the books) but the book is moving to the right, so there is NO work done.

You might be interested in

Between magnesium and calcium, which has the highest ionization energy, and why?

quester [9]

Answer:

magnesium

Explanation:

magnesium has fewer valence shells meaning that the protons have a stronger hold on the electrons and it would take more energy to remove an electron to create an ion.

3 0

3 years ago

In an experiment designed to determine the concentration of Cu 2 ions in an unknown solution, you need to prepare 100 mL of 0.10

Alexxandr [17]

Answer:

1.6 grams

Explanation:

We need to prepare 100 mL (0.100 L) of a 0.10 M CuSO₄ solution. The required moles of CuSO₄ are:

0.100 L × 0.10 mol/L = 0.010 mol

The molar mass of CuSO₄ is 159.61 g/mol. The mass corresponding to 0.010 moles is:

0.010 mol × (159.61 g/mol) = 1.6 g

We should use 1.6 grams of CuSO₄.

8 0

3 years ago

A molecule of glucose is comprised of 6 atoms of carbon, 12 atoms of hydrogen, and 6

Tanya [424]

Answer:

Explanation:

because you add 6 and 6 and 12 to get it

7 0

2 years ago

A 720. cm^3 vessel contains a mixture of Ar and Xe. If the mass of the gas mixture is 2.966 g at 25.0°C and the pressure is 760.

sleet_krkn [62]

Explanation:

The given data is as follows.

Pressure (P) = 760 torr = 1 atm

Volume (V) = $720 cm^{3}$ = 0.720 L

Temperature (T) = $25^{o}C$ = (25 + 273) K = 298 K

Using ideal gas equation, we will calculate the number of moles as follows.

PV = nRT

Total atoms present (n) = $\frac{PV}{RT}$

= $1 \times \frac{0.720 L}{0.0821 \times 298}$

= 0.0294 mol

Let us assume that there are x mol of Ar and y mol of Xe.

Hence, total number of moles will be as follows.

x + y = 0.0294

Also, 40x + 131y = 2.966

x = 0.0097 mol

y = (0.0294 - 0.0097)

= 0.0197 mol

Therefore, mole fraction will be calculated as follows.

Mol fraction of Xe = $\frac{y}{(x+y)}$

= $\frac{0.0197}{0.0294}$

= 0.67

Therefore, the mole fraction of Xe is 0.67.

6 0

3 years ago

An unknown triprotic acid (H3A) is titrated with NaOH. After the titration Ka1 is determined to be 0.0013 and Ka2 is determined

e-lub [12.9K]

Answer:

6.68 X 10^-11

Explanation:

From the second Ka, you can calculate pKa = -log (Ka2) = 6.187

The pH at the second equivalence point (8.181) will be the average of pKa2 and pKa3. So,

8.181 = (6.187 + pKa3) / 2

Solving gives pKa3 = 10.175, and Ka3 = 10^-pKa3 = 6.68 X 10^-11

7 0

3 years ago