1. the russian chemist who designed the first accepted version of periodic table in the 1800s was 2. the first accepted version of the periodic table was arranged by atomic mass, but the modern periodic table, that we use today, is arranged according who am i? identify the element using the information given below in questions 3-5. give the element symbol and be sure to write it in the correct format, for example: if the answer is bromine and you write br, it will be marked wrong, br is the correct element symbol. 3. i am in group 15 and period 3 4. i am in period 4 and group 13 5. i am in group 13 and period 2

The climate of the continental united states is generally 1. tropical 2. temperate 3. arctic 4. highland

98 points you will be galileo perform the experiment to determine if objects with different mass fall at the same, or different, rates in the air and in a vacuum. before you conduct your experiment, you need to form a hypothesis. a hypothesis is a prediction of what you think will happen in the experiment. the hypothesis is a statement that describes “if” a certain set of circumstances are present “then” there will be a specific result that will occur. record your hypothesis here: record the results from step one of the experiment (dropping the objects in the air): first trial: second trial: third trial: record the results from step two of the experiment (dropping the objects in a vacuum): first trial: second trial: third trial: did the experiment support your hypothesis? using the data from your experiment, describe why you believe your hypothesis was either proven or disproven. what forces were acting on the objects dropped in the air? what force was acting on the objects dropped in the vacuum? part two: comparing forces choose two forces and compare and contrast these forces. you must provide two ways that they are alike and two ways that they are different. you may make a list, write in paragraph form, or make a chart. choose two forces and compare and contrast these forces. these must be different forces than used in the prior question. provide two ways that they are similar and two ways that they are different. you may make a list, write it out, or make a chart.

The student repeated the experiment using a higher concentration of acid. the same volume of acid and the same mass of magnesium ribbon were used. what volume of hydrogen gas would have been produced after 60 seconds?