In the following reaction, oxygen is the excess reactant. (8 points) SiCl4 + O2 → SiO2 + Cl2

The table shows an experimental record for the above reaction.

Experimental Record
Trial Starting Amount of SiCl4 Starting Amount of O2 Actual Yield of SiO2
1 120 g 240 g 38.2 g
2 75 g 50 g 25.2 g
Calculate the percentage yield for SiO2 for Trial 1. Also, determine the leftover reactant for the trial. Show your work.
Based on the percentage yield in Trial 2, explain what ratio of reactants is more efficient for the given reaction.

The first element on the periodic table of elements is carbon. a. true b. false

Agroup of students is studying convection current. they fill two identical balloons with the same amount of helium. one balloon is placed in a freezer and the other is in an area with warm air. after 10 minutes, the balloon are released from a height of 1 meter. which of the following to the students most likely observe? a) the warm balloon expands and rises. the cold balloon shrinks and sinks b) the balloon both rise. the cold balloon is larger than the warm balloon c) the cold balloon expands and rises. the warm balloon shrinks and sinks d) the balloon rise at the same rate. both balloons are the same size

Acompound has a molar mass of 92.02 grams/mole, and its percent composition is 30.4% nitrogen (n) and 69.6% oxygen (o). what is its molecular formula? a. n2o4 b. no2 c. n2o d. n4o2