Answer:
Thermal energy in the form of heat moved from the fire to the skewer and marshmallow.
Explanation:
He holds a marshmallow on a metal skewer over a fire. A few seconds late, the marshmallow is cooked and the skewer feels warm.
Explanation:
Let the mass of isoamyl acetate be 100g.
Moles of Carbon = 60.58/12 = 5.048mol
Moles of Hydrogen = 7.07/1 = 7.07mol
Moles of Oxygen = 32.28/16 = 2.018mol
Mole Ratio of C : H : O
= 5.048 : 7.07 : 2.018
= 5 : 7 : 2.
Hence the empirical formula of isoamyl acetate is C5H7O2.
The right answer is screening test.
In medicine, screening consists of looking for one or more diseases or abnormalities known as "at risk" in individuals of a given population.
These investigations are followed or not by medical consultations, clinical examinations and treatments.
In addition, screening is a preliminary procedure (test or examination) to detect one or more characteristic signs or symptoms of a disease or syndrome and potentially leading to further investigation.
Answer:
Explanation:
From the net ionic equation
Ba2+(aq) + SO42-(aq) ==> BaSO4(s) we see that 1 mole Ba2+ reacts with 1 mole SO42- to -> 1 mol BaSO4
Find moles of Ba2+ used: 0.250 moles/L x 0.0323 L = 0.008075 moles Ba2+
Find moles SO42- present: 0.008075 moles Ba2+ x 1 mol SO42-/1 mol Ba2+ = 0.008075 mol SO42-
Find mass of Na2SO4 present: 0.008075 mol SO42- x 1 mol Na2SO4/1 mol SO42- x 142.04 Na2SO4/mole = 1.14698 g = 1.15 g Na2SO4 (to 3 significant figures)
The answer to your question is false, boiling happens below the surface of a substance.