Which of the following is not a correct chemical equation for a double displacement reaction? (d? )

2hno3 + mg(oh)2 yields 2h2o + mg(no3)2

h3po4 + 3naf yields 3hf + na3po4

2kno2 + baso4 yields k2so4 + ba(no2)2

4nabr + co(so3)2 yields br2so3 + cona4

An aqueous solution of hydroiodic acid is standardized by titration with a 0.186 m solution of calcium hydroxide. if 26.5 ml of base are required to neutralize 20.3 ml of the acid, what is the molarity of the hydroiodic acid solution? m hydroiodic acid

Listen base your answer to the question on the information below.propane is a fuel that is sold in rigid, pressurized cylinders. most of the propane in a cylinder is liquid, with gas in the space above the liquid level. when propane is released from the cylinder, the propane leaves the cylinder as a gas. propane gas is used as a fuel by mixing it with oxygen in the air and igniting the mixture, as represented by the balanced equation below.c3h8(g) + 5o2(g) → 3co2(g) + 4h2o() + 2219.2 kja small amount of methanethiol, which has a distinct odor, is added to the propane to consumers detect a propane leak. in methanethiol, the odor is caused by the thiol functional group (–sh). methanethiol, ch3sh, has a structure that is very similar to the structure of methanol.what is the correct structural formula for a molecule of methanethiol

Mike and mitchell decide to have a foot race. they mark off a stretch of 100 yards, and recruit cindy to work the stopwatch. after running the race and looking at the results, cindy declared that mitchell was the fastest. so how did the boys times compare?