The complete combustion of ethanol, C2H5OH (FW = 46.0 g/mol), proceeds as follows:

C2H5OH(l) + 3 O2(g) → 2 CO2(g) + 3 H2O(l) ΔH = -555 kJ

What is the enthalpy change for combustion of 4.0 moles of C2H5OH?
A) -2220 kJ
B) -139 kJ
C) 715 kJ
D) -82500 kJ

For a research project, a student decided to test the effect of the lead(ii) ion (pb2+) on the ability of salmon eggs to hatch. this ion was obtainable from the water‐soluble salt, lead(ii) nitrate, which the student decided to make by the following reaction. pbo(s) + 2 hno3(aq) → pb(no3)2(aq) + h2o losses of product for various reasons were expected, and a yield of 86.0% was expected. in order to have 5.00 g of product at this yield, how many grams of pbo should be reacted? (assume that sufficient nitric acid, hno3, would be used.)

If maltose undergoes hydrolysis what subunits does it results to?

Covalent compounds: mastery test select the correct answer what is formed when atoms join together with a covalent bond? a. an ion b. a molecule c. a neutral atom d. a noble gas