Pls help with science

Which of the following Group 17 elements is the least reactive?

satela [25.4K]

The given question is incomplete. The complete question is :

Which of the following Group 17 elements is the least reactive

a) Flourine

b) Chlorine

c) Astatine

d) Iodine

Answer: c) Astatine

Explanation:

Halogen is the name given to Group 17 family with general electronic configuration of $ns^2np^5$ which have 7 valence electrons and thus easily gain one electron to attain stable configuration.

As we move down the group from flourine to chlorine to bromine to iodine to astatine , the valence shell moves farther from nucleus and thus tendency to accept the electron decreases and thus reactivity also decreases.

Thus Astatine is the least reactive of all.

7 0

3 years ago

What type of compound is created when potassium and chlorine combine?

poizon [28]

Answer : The type of compound created is Ionic compound and the chemical formula is KCl.

Explanation :

Potassium has 1 electron in its valence shell and chlorine has 7 electrons in its valence shell.

The potassium loses 1 valence electron & make a positive charged ion and chlorine picks it up & make a negative charged ion and then they attract to each other.

Potassium and chlorine atom combine to form potassium chloride by the ionic bonding.

An ionic compound is made of a metal and non-metal element. And in this case, potassium is a metal element and chlorine is a non-metal element.

The ionic compound formation is,

$K+Cl\rightarrow KCl$

The Chemical formula is KCl.

3 0

3 years ago

Compound X has a molar mass of 135.13 and the following composition: element mass % carbon 44.44% hydrogen 3.73% nitrogen 51.83%

geniusboy [140]

Hello!

First, let's see what a molar mass is. A molar mass is how much a mole weighs, or how much 6.02214076×10²³ of an element weighs.

Now, let's find the molar mass of each of these three elements.

Carbon: 12.0107 g/mol

Hydrogen: 1.00784 g/mol

Nitrogen: 14.0067 g/mol

Now, see how much of the molar mass of compound x each of these contributes.

Carbon: 44.44% * 135.13 = 60.051772 g/mol

Hydrogen: 3.73% * 135.13 = 5.040349 g/mol

Nitrogen: 51.83% * 135.13 = 70.037879 g/mol

Finally, calculate how many atoms there are in the molecule. Do this my dividing the "how much they contribute to the molar mass" by the molar mass.

Carbon: 60.051772 / 12.0107 = 5

Hydrogen: 5.040349 / 1.00784 = 5

Nitrogen: 70.037879 / 14.0067 = 5

Therefore, we know that there are 5 Carbons, 5 hydrogens, and 5 nitrogens.

Put this all together to get the molecular formula: C5H5N5 (note that the numbers should be written as subscript)

Hope this helps!

7 0

3 years ago

If you were converting from milli- to centi- units, would you move the decimal point to the left or the right

yan [13]

Answer:

Left

Explanation:

6 0

3 years ago

Use the periodic table and example bond table to answer the question.

lyudmila [28]

In keeping with the general trends, K-Br will have the smallest bond energy. The bond energy refers to the energy that keeps the atoms in a bond together.

<h3>What is bond energy?</h3>

Bond energy is the energy that is required to hold atoms together in a bond. This energy must also be supplied when the atoms are to be separated.

We have the bond energies of each of the bons in the question, we have to note that the the smallest value of bond energy is Na-Br hence in keeping with the general trends, K-Br will have the smallest bond energy.

Learn more about bond energies: brainly.com/question/14842720?

7 0

2 years ago