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yulyashka [42]
3 years ago
15

How do you do these?

Chemistry
1 answer:
Agata [3.3K]3 years ago
6 0

Solve these problems like weighted averages:

The first one:

Multiply the masses (isotope numbers) by the decimal form of the percentage. Add them

0.076 (6) + 0.924 (7) = 6.924


The second one:

0.2 (10) + 0.8 (11) = 10.8


If you think about it, these answers make sense. 6.924 is much closer to 7 than to 6 (since there's a lot more lithium-7 than there is lithium-6). 10.8 is closer to 11 than to 10.


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You perform a distillation to separate a mixture of propylbenzene and cyclohexane, and you obtain 2.9949 grams of cyclohexane (d
Romashka-Z-Leto [24]

Answer:

66.67%

Explanation:

From the given information:

mass of cyclohexane = 2.9949 grams

density of cyclohexane = 0.779 g/mL

Recall that:

Density = mass/volume

∴

Volume = mass/density

So, the volume of cyclohexane = 2.9949 g/ 0.779 g/mL

= 3.8445 mL

Also,

mass of propylbenzene = 1.6575 grams

density of propylbenzene = 0.862 g/mL

Volume of propylbenzene =  1.6575 g/ 0.862 g/mL

= 1.9229 mL

The volume % composition of cyclohexane from the mixture is:

= (\dfrac{v_{cyclohexane}}{v_{cyclohexane}+v_{propylbenzene}})\times 100

= (\dfrac{3.8445}{3.8445+1.9229})\times 100

= (\dfrac{3.8445}{5.7674})\times 100

= 66.67%

6 0
3 years ago
Determine the mass of a ball with a wavelength of 3.45 × 10-34 m and a velocity of 6.55 m/s
Yuki888 [10]
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6 0
3 years ago
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dalvyx [7]

Explanation:

The given data is as follows.

      V_{1} = 250 mL,     V_{2} = 750 mL

      T_{1} = 35^{o}C = 35 + 273 K = 308 K

      T_{2} = 35 + 273 K = 308 K

      P_{1} = 0.55 atm,    P_{2} = 1.5 atm

               P = ? ,         V = 10.0 L

Since, temperature is constant.

So,    P_{1}V_{1} + P_{2}V_{2} = PV

Now, putting the given values into the above formula as follows.

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As, 1 atm = 760 torr. So, 0.126 atm \times \frac{760 torr}{1 atm} = 95.76 torr.

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8 0
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Which of these is an example of heat transferred by radiation?
timofeeve [1]
A I think I’m not sure
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Mice21 [21]

Answer:

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Explanation:

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Types of chemical bond

There are four types of chemical bonds

- covalent bond

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Ionic bond involves the transfer of an electron which involves one atom receiving and the other giving out

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