All categories

2 years ago

All of the noble gasses have 8 valence electrons except _____. helium argon xenon neon this is science

Chemistry

2 answers:

pogonyaev2 years ago

5 0

<span>Helium is the noble gas with only 2 valence electrons

I Hope This helps

</span>

Tomtit [17]2 years ago

5 0

Helium because it has 2 electrons
just like the photo

You might be interested in

What is the change in the enthalpy of 120 g/s acid heated in a double pipe heat exchanger from 25°C to 100°C, if the average hea

telo118 [61]

Answer:

ojopjd

Explanation:

3 0

2 years ago

Heavy elements, like uranium, were/are created _______________. a. in supernovae and star collisions b. all of the above c. in t

Ivenika [448]

Answer:

a. in supernovae and star collisions

Explanation:

The periodical table contains some heavier elements, which are formed as neutron stars pairs hit eachother and erupt cataclysmically.

The star emitts very large quantities of energy and neutrons during supernova, which allow for the production of heavier elements than iron, such as uranium and gold. All these elements are ejected into space during the supernova explosion.

3 0

2 years ago

An unbalanced chemical equation is shown:

Sati [7]

Answer:

1. Two to decompose

Explanation:

It's going to be a decomposition so you can eliminate answers 3 and 4. It is a decomposition because it is splitting apart. Then you can figure out that it is going to be two instead of four by balancing the equation

H2O2 → 2H2O + O2

$2H_{2}O_{2} → 2H_{2}O + O_{2}$

6 0

2 years ago

Read 2 more answers

How many grams of oxygen (O) are present in 0.0207 moles of Ca(HCO 3) 2

Zolol [24]

Answer:

1.99grams

Explanation:

- First, we need to calculate the molar mass of the compound: Ca(HCO3)2

Ca = 40g/mol, H = 1g/mol, C = 12g/mol, O = 16g/mol

Hence, Ca(HCO3)2

= 40 + {1 + 12 + 16(3)}2

= 40 + {13 + 48}2

= 40 + {61}2

= 40 + 122

= 162g/mol

Molar mass of Ca(HCO3)2 = 162g/mol

- Next, we calculate the mass of oxygen in one mole of the compound, Ca(HCO3)2.

Oxygen = {16(3)}2

= 48 × 2

= 96g of Oxygen

- Next, we calculate the percentage composition of oxygen by mass by dividing the mass of oxygen in the compound by the molar mass of the compound i.e.

% composition of O = 96/162 × 100

= 0.5926 × 100

= 59.26%.

- The number of moles of the compound, Ca(HCO3)2, must be converted to mass by using the formula; mole = mass/molar mass

0.0207 = mass/162

Mass = 162 × 0.0207

Mass = 3.353grams

However, in every gram of Ca(HCO3)2, there is 0.5926 g of oxygen

Hence, in 3.353grams of Ca(HCO3)2, there will be;

0.5926 × 3.353

= 1.986

= 1.99grams.

Therefore, there is 1.99grams of Oxygen in 0.0207 moles (3.353g) of Ca(HCO3)2.

5 0

2 years ago

Linolenic acid has cis double bonds with the formula ch3ch2ch=chch2ch=chch2ch=ch(ch2)7cooh. write out the abbreviated systematic

valentinak56 [21]

<span>Abbreviated systematic numbering for Linolenic Acid is,

18:3, n-3
Explanation:
In above abbreviation 18 specifies number of carbon atoms in Linolenic Acid, 3 specifies the number of double bonds and n-3 specifies the position of first double bond from methyl end. The structure of Linolenic Acid is as follow,</span>

3 0

2 years ago