In a gas chromatography experiment, a mixture of two compounds (a and b) was separated for analysis. a chart recorder that fed paper at a constant rate of 100 mm. per minute was used to record the chromatogram, and a mark was made on the chart at the time the sample was injected. the first peak on the chromatogram corresponds to compound a, and that peak was observed at a distance of 5.19 cm from the sample injection point, and it had a height of 3.05 cm and a width at half-height of 1.16 cm. the peak corresponding to b was observed at a distance of 8.23 cm from the injection point, and it had a height of 4 cm and a width at half-height of 1.9 cm. what was the retention time for compound b (in seconds)? (enter your answer as a number only.)

Acontrol during an experiment. might change remains constant does not exist does change

For a family dinner, jose’s mom baked a loaf of bread. during the meal, his grandmother commented, “this bread is so dense! ” what do you think his grandmother meant by the word dense? you have some ideas regarding density already, but this experiment will enrich your understanding of the relationship between mass, volume and the density of objects. when making measurements in this experiment we will be using si units, the international system of units. the purpose of using si units is to have the ability to communicate and compare data results with other experiments without having to make conversions. measurement symbol si unit length m meter mass kg kilogram volume l liters density kg/l kilograms per liter any calculations that are performed during this experiment will ultimately be reported in scientific notation. recall that scientific notation is extremely important when we have data that is extremely small or large. scientists rely on a standard form of communication to quickly make hypotheses and judgements based on data. what is the density of block a? a0kg/l what is the density of block b? a1kg/l what is the density of block c? a2kg/l what is the density of block d? a3kg/l what is the density of block e? a4kg/l which block is the densest? a5

Why do oxygen have a strong attractive force for electrons