Answer:
All matter is made up of substances called elements, which have specific chemical and physical properties and can't be broken down into other substances through ordinary chemical reactions. Gold, in this case, is an element so, therefore, it is considered matter.
Hope it helped :)
The brain is part of the central nervous system.
Nerves and sensors are part of the peripheral nervous system. Only the brain and spinal cord make the central nervous system.
The first thing you do before performing anything in the laboratory is to read the procedure and prepare the materials needed. Next, if you already have the solution where you are supposed to take your 20 mL sample, then have it near you. Then, prepare a volumetric flask (750 mL) and a 20-mL pipette. Wash the pipette 3 times with the sample solution. If your diluent is water, wash the flask 3 times with water. Now, get 20 mL of sample from your parent solution, then add it to the flask (previously washed with water). Finally, add water until the mark in the flask and make sure that the water added is up to the mark based on the lower meniscus reading to be accurate in the amount inside the flask. <span />
Answer:
-608KJ/mol
Explanation:
3 C2H2(g) -> C6H6(g)
ΔHrxn = ΔHproduct - ΔHreactant
ΔHrxn= ΔHC6H6 - 3ΔHC2H2
ΔHrxn = 83 - 3(230)
ΔHrxn = -608
