Pb (NO3) 2 10. A compound is 42.3 % C, 5.94 % H, 32.9 % N, and 18.8 % O and has a molecular mass of 425.25 g/mol. Calculate the empirical and molecular formula. C15H25N10O5 11. How many moles of Al2O3 are produced by the reaction 200. g Al?
Yes, scientists can use more than one type of isotope to date the same rock or fossil because some can form around the same time and some can’t. 6.) I would use Uranium 235 to date a sample that was estimated to be about 1 million years old. I would use Uranium 235 because Uranium is used to date back fossils from millions of years ago and because uranium’s half life is closer to 1 million than Thorium 232. Conclusion: A half life is the time required for half of the unstable isotope to change into a stable decay product.
1) The statement that determines if the null hypothesis is rejected or not is called the A. critical value B. alternate hypothesis C. test statistic D. decision rule 2) The normally distributed AAA battery life is stated to be 350 days when used in a clock radio. The Big Charge Battery Company has recently modified the AAA batteries so as to extent their life. The owner of the company wanted to know if the improved batteries really did last significantly longer. A sample of 100 of the improved batteries was tested. It was discovered that the mean life was 362 days and the sample standard deviation was 10 days.
Conclusion 10 Grams of Potassium chlorate when decomposed produces 3.915576 grams oxygen gas and 6.083363 grams potassium chloride Atomic Weight of Magnesium Introduction In this lab we will determine the atomic weight of magnesium by measuring the amount of hydrogen gas evolved when hydrochloric acid reacts with magnesium. The reaction is as follows: Mg + 2HCl -> H2 + Mg2+ (aq) + 2Cl- (aq) There is a one to one relationship between the number of moles of hydrogen gas evolved and the
Seventy five percent of the table is made up of metals, and a couple of the columns on the right of the table have gases. There are only two elements that are liquids- mercury and bromine. Column 1 contains the alkali metals, which suddenly combust when exposed to air or water. Columns 3-12 are the transition metals, which contain heavier atoms, which are more flexible in how they organize their electrons. Column 17 is made up of the more reactive gases- the halogens.
How many kilograms of pure HCl would be used to make this hydrochloric acid? (Assume that 30% has two significant figures. There are 2000 lb/ton.) (Obj 15) 30 ton HCl 2000 lb 1 kg ? kg HCl = 6.0 × 105 ton HCl soln 100 ton HCl soln 1 ton 2.205 lb 30 ton HCl 2000 lb 453.6 g 1 kg ?
0 N, 180 W c. 60 N, 120 E [pic] d. 0 N, 30 W 9. How many times larger is a magnitude 3 than a magnitude 1 earthquake on the Richter scale? [pic] a. 10 times b. 100 000 times c. 1/10 times [pic] d. 100 times 10.
The goal formally was to lose or gain no more than one out of every billion billion seconds. That is one second in about 32 billion years, and is 10 to 100 times better than any existing clocks. Already, atomic clocks have come a long way. While experimental clocks are moving ahead, a device called the NIST-F1 is the official U.S. timekeeper. It’s accurate to a few parts in 1016.
It has a melting point of 1585K (which is the same as 1312°C 2394°F), heat of fusion of 10,05 kJ/mol, and boiling point of 3546 K( 3273 °C, 5923 °F). Gadolinium has an electron configuration of [Xe]4f 75d16s2; and vapour pressure of7.39 Pa at temperatures of 2000 K.
CHEMISTRY OF COPPER Introduction Copper is a chemical element with the symbol Cu and atomic number 29. It is a ductilemetal with very high thermal and electrical conductivity. Pure copper is soft and malleable; an exposed surface has a reddish-orange tarnish. It is used as a conductor of heat and electricity, a building material, and a constituent of various metal alloys. Copper was the first metal mined and crafted by man, and has been the most important one in the oldest times of history, because it was available in great quantities and was initially extractable almost at the surface of ground.