All categories

3 years ago

WHAT IS A PLACE WHERE BOOKS ARE CLASSIFIED! I NEED HELP!

Chemistry

2 answers:

alexdok [17]3 years ago

8 0

Answer:

From the Online Catalog to the Shelf

Libraries in the United States generally use either the Library of Congress Classification System (LC) or the Dewey Decimal Classification System to organize their books. Most academic libraries use LC, and most public libraries and K-12 school libraries use Dewey.

jasenka [17]3 years ago

5 0

Answer:

From the Online Catalog to the Shelf

Explanation:

You might be interested in

How many moles of carbon are in the sample?

jeka94

????????????????????????????????????????????????????

5 0

3 years ago

Which best describes the importance of the microscope to the development of cell theory? Microscopes color different parts of ce

aliya0001 [1]

Cells are too small to see with the naked eye.

It's pretty straight forward, use the cross-out method.

1) Microscopes MAGNIFY images, they don't color the cells. In fact, scientists have to use these chemicals to "stain" or color the cells to see them more easily through microscopes.

2) If the lenses of a microscope reduced the image of an organism to the size of a cell, you'd be seeing a very tiny human through your microscope, instead of actual cells.

3) Microscopes don't "trap" anything. In fact, scientists use plates or slides under microscopes to contain what they're studying.

8 0

3 years ago

Read 2 more answers

Are the following quantum number combinations allowed? If not, show two ways to correct them:

evablogger [386]

Answer:

(a) n = 2; l = 0; ml = -1 ⇒ WRONG

change ml = 0, or l = 1 to correct.

(b) n = 4, l = 3; ml = -1 ⇒ CORRECT

(d) n = 5, l = 2; ml = +3 ⇒ WRONG

change ml = 0, ±1 or ±2, or l = 3 or l = 4 to correct.

Explanation:

The rules for electron quantum numbers are:

1. Shell number, 1 ≤ n

2. Subshell number, 0 ≤ l ≤ n − 1

3. Orbital energy shift, -l ≤ ml ≤ l

4. Spin, either -1/2 or +1/2

Now, apply in our case

(a) n = 2; l = 0; ml = -1 ⇒ WRONG

-l ≤ ml ≤ l, so either change ml = 0 or l = 1 to correct.

(b) n = 4, l = 3; ml = -1 ⇒ CORRECT

(d) n = 5, l = 2; ml = +3 ⇒ WRONG

-l ≤ ml ≤ l, so either change ml = 0, ±1 or ±2, or l = 3 or l = 4 to correct.

7 0

3 years ago

A sample of an unknown compound was decomposed and found to be composed of 1.36 mol oxygen, 4.10 mol hydrogen, and 2.05 mol carb

AfilCa [17]

We are given the number of moles:

O = 1.36 mol

H = 4.10 mol

C = 2.05 mol

To get the empirical formula, first divide everything by the smallest number of moles = 1.36 mol. So that:

O = 1 mol

H = 3 mol

C = 1.5 mol

Next step is to multiply everything by a number such that all will be a whole number. In this case, multiply by 2 to get a whole number for C, so that:

O = 2 mol

H = 6 mol

C = 3 mol

Therefore the empirical formula of the compound is:

C3H6O2

8 0

4 years ago

How many moles of aluminum oxide (Al2O3) are in a sample with a mass of 204. 0 g? 1. 000 2. 000 3. 0.

Aleks [24]

Answer:

1. 000.2

Explanation:

 aluminum oxide made of moles or atoms less then other elements need to decrease

6 0

3 years ago