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3 years ago

What’s the symbol of the element that has 8 protons, 9 neutrons, and 8 electrons

Chemistry

1 answer:

Katena32 [7]3 years ago

7 0

Answer:

oxygen

Explanation:

The given isotope has 8 protons and 8 electrons, so the atomic number of the given isotope is 8, which is the atomic number of oxygen.

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Part I: Multiple Choice Questlons

mina [271]

Answer:

A cuz a heterogeneous mixture is no uniform

7 0

3 years ago

Read 2 more answers

If you have a truckload of icecream, a bucket of sauce, a box of peanuts but only 1 cherry, you can only make 1 complete sundae.

MAXImum [283]

Answer:

Only 5 sundaes can be made

The limiting reagent is the peanuts.

Explanation:

The complete question is

A perfect ice cream sundae requires exactly:

• 3 scoops of ice cream

• 2 squirts of chocolate sauce

• 1 spoon of peanuts

• 1 cherry

If you have 7 scoops of ice cream, 3 spoons of peanuts, 5 cherries and 11 squirts of sauce, you can only

make 2 complete sundaes. In this case, the icecream is the limiting reagent.

If you have a truckload of icecream, a bucket of sauce, a box of peanuts but only 1 cherry, you can only make 1 complete sundae. In this case the cherry is the limiting reagent. The limiting reagent is the term given to the ingredient (read: reactant) that has the (stoichiometrically) least amount. The other reactants are said to be in excess. In a reaction the limiting reagent will be totally consumed, and some of the reactant in excess will be leftover.

Critical thinking questions

1. If you have 20 scoops of ice cream, 14 squirts of chocolate sauce, 5 spoons of peanuts and 7 cherries,

how many sundaes can you make and which ingredient is the limiting reagent?

From the ingredients for a a complete sundae given above,

20 scoops of icecream will make 20/3 = 6.66 sundaes

14 squirts of chocolate sauce will make 14/2 = 7 sundaes

5 spoonful of peanuts will make 5/1 = 5 sundaes

7 cherries will make 7/1 = 7 sundaes

From the above, we can work out that only 5 sundaes can be made, and the limiting agent here is peanuts, which has the least amount of sundae that can be made from its available amount.

5 0

3 years ago

Baking soda (nahco3) is an active ingredient in some antacids. determine the percent composition of oxygen in baking soda.

telo118 [61]

Assuming the question is asking for percent composition by mass,

The molar mass of sodium bicarbonate is:

22.990 + 1.008 + 12.011 + 3*15.999 = 84.006 g/mol

The molar mass of 3 oxygen atoms is:

3*15.999 = 47.997 g/mol

The percentage composition by mass is:

47.997/84.006 * 100% = 57.1% (3 s.f.)

8 0

3 years ago

What can happen when chlorine is left in drinking water

lawyer [7]

Chlorine is used in swimming pools to kill unwanted bacteria and keep swimmers safe from infections and disease from the water. While there isn't enough chlorine in swimming pools to cause permanent damage, it can leave your hair dry and your skin irritated and red.

4 0

3 years ago

Arrange the elements in decreasing order of first ionization energy.

just olya [345]

Answer:

The decreasing order of first ionization energy: Se > Ge > In > Cs

The decreasing order of first ionization energy: x > y > z

Explanation:

Ionization energy refers to the energy needed to completely pull out an electron from the valence shell of a neutral gaseous atom.

First ionization energy is the energy involved in the removal of first valence electron.

In the periodic table, down the group, as atomic radius of elements increases, the ionization energy decreases

Whereas, across a period, as atomic radius of elements decreases, the ionization energy increases.

PART (A):

Position of the given elements in the periodic table:

Indium (In): Group 13, period 5

Germanium (Ge): Group 14, period 4

Selenium (Se): Group 16, period 4

Caesium (Cs): Group 1, period 6

Thus, the increasing order of atomic radius: Se < Ge < In < Cs

Therefore, the decreasing order of first ionization energy: Se > Ge > In > Cs

PART (B):

Given elements:

element x: radius = 110 pm

element y: radius = 199 pm

element z: radius = 257 pm

Thus, the increasing order of atomic radius: x < y < z

Therefore, the decreasing order of first ionization energy: x > y > z

5 0

3 years ago