Help me will mark brainliest
Matching: Label each of the following reaction or change as chemi...
Mathematics, 29.05.2020 06:57 123userhi
Help me will mark brainliest
Matching: Label each of the following reaction or change as chemical or physical.
Question 13 options:
copper plating a nail
cooking an egg
wood burning
water boiling
making Kool Aid
melting sand to make glass
1.
chemical change
2.
physical change
Question 14 (Mandatory) (2 points)
In an ionic bond, electrons are .
Question 14 options:
gained or lost
given to noble gases
moved to inner shells/orbitals
shared
Question 15 (Mandatory) (2 points)
What happens when an acid is mixed with a base?
Question 15 options:
they will neutralize each other
they will form a gas
they will form a stronger acid
they will form a stronger base
Question 16 (Mandatory) (2 points)
How many valence electrons do most atoms need to have in their outer shell to be most stable?
Question 16 options:
8
1
4
6
Question 17 (Mandatory) (2 points)
Metals tend to electrons and become .
Question 17 options:
lose, cations
lose, anions
gain, cations
gain, anions
Question 18 (Mandatory) (2 points)
What does a chemical change always result in?
Question 18 options:
new reactant
increased activation energy
new substance
precipitate
Question 19 (Mandatory) (2 points)
Question 19 options:
Fill in the blank: What is the correct name for the ionic compound Ca2P5?
Question 20 (Mandatory) (2 points)
Which is NOT evidence of a chemical reaction?
Question 20 options:
precipitate formed
melting
bubbles
color change
Question 21 (Mandatory) (2 points)
What happens in a covalent bond between atoms?
Question 21 options:
the smaller atom’s neutrons repel the electrons
the electrons flow in an electric current away from the bonded pair of atoms
electrons are lost by one atom and gained by the other
each atom shares electrons so that they are both stable
Question 22 (Mandatory) (2 points)
The on the left side of an equation must be balanced with the atoms on the right side of the equation.
Question 22 options:
total number of compounds
total number of molecules
free electrons
total number of atoms
Question 23 (Mandatory) (2 points)
Which of the following equations is balanced?
Question 23 options:
H2 + O2 → H2O + O
4H2 + O2 → H2O + O
2H2 + O2 → 2H2O
H2 + O2 → H2O
Question 24 (Mandatory) (2 points)
What is pH?
Question 24 options:
how basic a solution is
how acidic a solution is
the concentration of hydroxide ions in a solution
the concentration of hydrogen ions in a solution
Question 25 (Mandatory) (2 points)
Choose the equation below that is balanced correctly.
Question 25 options:
S8 + 12 O2 Ã 8 SO3
2 S8 + 3 O2 Ã 2 SO3
S8 + 24 O2 Ã 8 SO3
6 S8 + 8 O2 Ã 6 SO3
Answers: 3
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Answers: 3
Mathematics, 21.06.2019 20:30
Two angles are complementary. the larger angle is 36 more than the smaller angle. what is the measure of the larger angle?
Answers: 2
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