Do electrons fill up the lowest or highest level

Determine the number of HC=CH, monomeric units in one molecule of polyethylene with a molar mass of 13,500 g. _units?

Which of the following statements is true? All of the sun's radiation is reflected back into space by the Earth's atmosphere. Air is a good insulator because the molecules in gas are very far apart. Work can only be done by potential energy.

In which type of reaction do two lighter nuclei combine to form one heavier nucleus? (1) combustion (3) nuclear fission (2) reduction (4) nuclear fusion

Addition of an excess of lead (II) nitrate to a 50.0mL solution of magnesium chloride caused a formation of 7.35g of lead (II) chloride precipitate. What was the molar concentration of chloride ions in the solution (in mol/L) ?

Consider the equation CO2 - --> C + O2. What type of reaction is this? synthesis decomposition single displacement double displacement

Why is it possible to safely drink a solution that contains a 50:50 mixture of equal concentrations of a strong acid and a strong base, either of which, if ingested separately, would be very caustic and damaging?

Explain why many compounds that contain one or more hydrogen atoms are not classified as arrhenius acids

pure substance x is a green powder. when heated, it gives off a gas and changes to a black powder. is substance x an element or a compound? give reasons

What amount (moles) is represented by each of these samples? a. 20.0 mg caffeine, c8h10n4o2 b. 2.72 1021 mo?

A sample of gas occupies 40.0 mL at - 123°C. What volume does the sample occupy at 27°C if the pressure is held constant? V1T2 = V2T1 Don't forget to convert temperature to kelvin! Group of answer choices 8.80 mL 20.0 mL 80. ML 182 mL