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3 years ago

A nanotechnology equipment requires 7.40 x 10^18 atoms of potassium. What is the mass of this sample?

Chemistry

1 answer:

abruzzese [7]3 years ago

5 0

Answer:

4.81×10⁻⁴ g K

Explanation:

Convert atoms to moles:

7.40×10¹⁸ atoms K × (1 mol K / 6.02×10²³ atoms) = 1.23×10⁻⁵ mol K

Convert moles to mass:

1.23×10⁻⁵ mol K × (39.1 g K / mol K) = 4.81×10⁻⁴ g K

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2 years ago

Imagine you are an astronaut and you travel to a planet with a much larger mass than Earth. How would this affect your weight? E

Svetllana [295]

Answer:

Explanation:

It may not make any difference. The information missing is the radius of the planet.

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2 years ago

Why is the answer C for this problem?

pshichka [43]

Answer:

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Explanation:

Step 1. Identify the Group that contains X

We look at the consecutive ionization energies and hunt for a big jump between them

$\begin{array}{crc}n & IE_{n} & IE_{n} - IE_{n-1}\\1 & 730 & \\2 & 1450 & 720\\3 & 7700 & 6250\\4 & 10500 & 2800\\\end{array}$

We see a big jump between n = 2 and n = 3. This indicates that X has two valence electrons.

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So, X is in Group 2 and P is in Group 15.

Step 2. Identify the Compound

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We must have 3 X atoms for every 2 P atoms.

The formula of the compound is $\boxed{\text{X}$_{3}$P$_{2}}$}$ .

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2 years ago

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elena-s [515]

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2 years ago

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2 years ago