Answer
Negative 5 and StartFraction 7 over 8 EndFractionfeet
Answer:
a: chemical change because the change cannot be reversed.
b: physical change because the action can be reversed.
c: chemical change.
d:chemical change.
any change that cannot be reversed is a chemical change and any change that can be reversed is a physical change.
Answer:
V HCNsln = 0.9176 L
Explanation:
V HCNsln = ?
∴ m HCN = 31 g
∴ <em>C</em> HCNsln = 1.25 mol/L
∴ molar mass HCN = 27.0253 g/mol
⇒ V HCNsln = (31 g)*(mol/27.0253 g)*(L/1.25 mol) = 0.9176 Lsln
Because the formation of rust is a kind of chemistry reaction.
After chemistry reaction, compound with new properties is produced.
Of course, color is one of the new properties.
For example, if you put iron in colorless acid solution, a green solution is made.
This kind of chemisty reaction differs from physical reaction, for example, pigment with one color dissolves in liquid, a liquid with same color is made.
