Question

What is the major difference between chemical and physical changes?
A. Chemical changes always involve the release of some gas, which is not the case with physical changes.
B. Physical changes always involve the release of some gas, which is not the case with chemical changes.
C. New substances are always produced in chemical changes, which is not the case with physical changes.
D. New substance are always produced in physical changes, which is not the case with chemical changes.

Answer 1

Which one do you think?

Answer 2

C. New substances are always produced in chemical changes, which is not the case with physical changes. Remember that.....forever :}

Answer 3

i was going to say a

Answer 4

The nucleus of an atom contains ________.

Answer 5

protons, and neutrons

Answer 6

electrons surround it, however

Answer 7

__________ are the simplest forms of matter that can exist under normal laboratory conditions.

Answer 8

elements, my friend

Answer 9

@Mertsj this would b elements right?

Answer 10

okay.

Answer 11

:}

Answer 12

A molecule with one end positively charged and one end negatively charged is said to be a __________ molecule.

Answer 13

Polar molecule

Answer 14

Which of the following statements distinguishes between scientific hypotheses and scientific theories?
A. A hypothesis is an explanation for an observation that has been tested. A theory is an explanation for an observation that has not been tested.
B. A hypothesis describes an observation that has been repeatedly observed by many scientists. A theory is an explanation for an observation that has not been tested.
C. A hypothesis is an explanation for an observation that has not been tested. A theory is an idea that has been repeatedly tested through scientific experimentation.
D. A hypothesis describes an observation that has been repeatedly observed by many scientists. A theory is an idea that has been repeatedly tested through scientific experimentation.

Answer 15

D makes the most sense

Answer 16

okay cool.

Answer 17

Some scientists believe that ___________ were once independent organisms because they contain their own genetic information.
A. leukoplasts
B. lysosomes
C. endoplasmic reticula
D. mitochondria

Answer 18

leukoplasts right?

Answer 19

hmmm.....i think so - dont remember though.....

Answer 20

Protein can be broken down into:
A. sugar
B. starch
C. amino acids
D. carbohydrates

Answer 21

C. amino acids

Answer 22

When ionic compounds dissolve in water, they often dissociate (break apart) into individual
A. molecular compounds.
B. ions.
C. isotopes.
D. suspensions.

Answer 23

ions

Answer 24

http://roads.advancedacademics.com/contentserver/content/roadssection/163372/water_molecule.gif

The part of a water molecule nearest the oxygen atom and farthest away from the hydrogen atoms has a(n)
A. slight positive charge.
B. slight negative charge.
C. no charge.
D. uneven distribution of charges.

Answer 25

i think B

Answer 26

okie

Answer 27

Which of these statements is true about all organisms?
A. Organisms are made of cells.
B. Organisms get all their nutrients from the sun.
C. Organisms have lungs.
D. Organisms live in small groups.

Answer 28

a

Answer 29

plants dont have lungs -

Answer 30

ahhh. true

Answer 31

humans dont live in small groups

Answer 32

we dont get our nutrients from the sun, like plants

Answer 33

that is true.. i have 3 more u up for it?

Answer 34

haha yea

Answer 35

In a solution, the part that does the dissolving is called the
A. solvent.
B. solute.
C. suspension.
D. dissolver.

Answer 36

d.
right

Answer 37

no solute i think

Answer 38

solute , yes

Answer 39

The cell membrane is made up of a bilayer of substances called _____________.
A. chlorophyll
B. chromoplasts
C. cellulose
D. phospholipids

Answer 40

phospholipids

Answer 41

What is the basic unit of structure and function in living things?

A. cell
B. tissue
C. organ
D. organ system



a right?

Answer 42

yes, a cell

Answer 43

okay cool. thanks for your help!

Answer 44

you're welcome :}