Answer:
Explanation:
%Carbon = mass of carbon / mas of C13H18O2) X100%
= 13X12/ (13X12+18+2X16)X100%
= 156/206) X100%= 75.7%
Arenal Volcano: Plate Tectonic Setting. The volcanic arc of Costa Rica, where Arenal is located, is a chain of mountains resulting from the subduction of the Cocos tectonic plate under the Caribbean Plate. Costa Rica is part of the Central American isthmus, which connects the North and South American continents.
Answer: 42.14 g
Explanation: calcium nitrate - 
, the molar mass of calcium nitrate = 164 g
<h3> formula used =

= no of moles </h3>
mass required =
=
g
Answer:
There are five signs of a chemical change:
Colour Change.
Production of an odour.
Change of Temperature.
Evolution of a gas (formation of bubbles)
Precipitate (formation of a solid).