3 years ago

What is the period number in which helium is found

2 answers:

6 0

Answer:

Helium is the second element on the periodic table. It is located in period 1 and group 18 or 8A on the righthand side of the table. This group contains the noble gases, which are the most chemically inert elements on the periodic table. Each He atom has two protons and usually two neutrons and two electrons.

Explanation:

thoughtco.com

GaryK [48]3 years ago

5 0

Answer:

period 1 and group 18 or 8A on the righthand side of the table.

Explanation:

You might be interested in

2000 km/sec. Convert that to m/sec.

koban [17]

Answer:

2000 km/sec

1km=1000m

2000×1000

2000,000 m/sec

4 0

4 years ago

Which element has the lowest first ionization energy? Be Sr OCa Mg

Dmitrij [34]

Answer
I think Sr
Hope this help!

5 0

3 years ago

An x-ray has a wavelength

goldfiish [28.3K]

Answer:

Explanation:

For electromagnetic waves frequency X wavelength = speed of light

f * 2.2 x 10^-11 = 3 x 10^8 m/s

f = 3 x 10^8 / 2.2 x 10^-11

= 1.36 x 10 ^19

= 1.4 x 10^19 with two significant digits

5 0

2 years ago

Which of the following sentences best describes what is shown in the above picture?

velikii [3]

Answer:

Cells of a multicellular organism

5 0

3 years ago

Read 2 more answers

How many moles are in 25.90 grams of NaCl

inessss [21]

Answer:

0.44316859040048207mol

Explanation:

7 0

3 years ago