Which scientist developed a new model of planetary motion?

What is the composition, in atom percent, of an alloy that consists of 4.5 wt% pb and 95.5 wt% sn? the atomic weights for pb and sn are 207.19 g/mol and 118.71 g/mol, respectively.(a) 2.6 at% pb and 97.4 at% sn(b) 7.6 at% pb and 92.4 at% sn(c)97.4 at% pb and 2.6 at% sn(d) 92.4 at% pb and 7.6 at% sn

6. what does the symbol ah stand for? o one calorie given off by a reaction the specific heat of a substance the heat capacity of a substance the heat of reaction for a chemical reaction

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