Chemistry is the study of all of the following EXCEPT

Why is tape attracted to my skin? Give explanation

shutvik [7]

Answer:

Since the tape has extra electrons, it has a negative charge. When you move your finger close to the tape, electrons in your skin are repelled and move away. This makes the skin on your finger tip have a slight positive charge. Since positive and negative attract, the tape moves toward your finger.

5 0

3 years ago

A compound is found to be 38.76% calcium, 19.97% phosphorous and 41.28% oxygen. What is the empirical formula for this compound?

motikmotik

The empirical formula is Ca₃P₂O₈.

Assume that you have 100 g of the compound.

Then you have 38.76 g Ca, 19.97 g P, and 41.28 g O.

Now, we must convert these masses to moles and find their ratios.

If the number in the ratio are not close to integers, you multiply them by a number that makes them close to integers.

From here on, I like to summarize the calculations in a table.

Element Mass/g Moles Ratio ×2 Integers

Ca 38.76 0.967 07 1.4998 2.9995 3

P 19.97 0.644 82 1 2 2

O 41.28 2.580 0 4.0011 8.0023 8

The empirical formula is Ca₃P₂O₈.

3 0

3 years ago

Given the wavelength of the corresponding emission line, calculate the equivalent radiated energy from n = 4 to n = 2 in both jo

lions [1.4K]

Explanation:

It is given that,

Initial orbit of electrons, $n_i=4$

Final orbit of electrons, $n_f=2$

We need to find energy, wavelength and frequency of the wave.

When atom make transition from one orbit to another, the energy of wave is given by :

$E=-13.6(\dfrac{1}{n_f^2}-\dfrac{1}{n_i^2})$

Putting all the values we get :

$E=-13.6(\dfrac{1}{(4)^2}-\dfrac{1}{(2)^2})\\\\E=2.55\ eV$

We know that : $1\ eV=1.6\times 10^{-19}\ J$

So,

$E=2.55\times 1.6\times 10^{-19}\\\\E=4.08\times 10^{-19}\ J$

Energy of wave in terms of frequency is given by :

$E=hf$

$f=\dfrac{E}{h}\\\\f=\dfrac{4.08\times 10^{-19}}{6.63\times 10^{-34}}\\\\f=6.14\times 10^{14}\ Hz$

Also, $c=f\lambda$

$\lambda$ is wavelength

So,

$\lambda=\dfrac{c}{f}\\\\\lambda=\dfrac{3\times 10^8}{6.14\times 10^{14}}\\\\\lambda=4.88\times 10^{-7}\ m\\\\\lambda=488\ nm$

Hence, this is the required solution.

4 0

3 years ago

The oxidation numbers of nitrogen in NH4+, N2O5, and NaNO3 are, respectively:

Andrew [12]

-III I
NH₄⁺

V -II
N₂O₅

I V -II
NaNO₃
-----------------------

-3 +5 +5

6 0

3 years ago

Read 2 more answers

Granite forms when magma cools slowly underground. Granite _____.

katrin [286]

Granite forms when magma cools slowly underground. Granite is an intrusive igneous rock. The answer is letter B. granite is composed mostly of quartz and feldspar with minor amounts of mica, amphiboles and other minerals.

3 0

3 years ago