Average Atomic Mass Cakulate the average atomic mass of the following imaginary elements based on the information supplied. % occurrence isotope mass 1. Zb-318 34.71 317.999785 Zb-32 o 43.61 319.989061 Zb-322 21.68 322000088 2. Omg -420 20.05 419.979962 Omg-424 39.21 424.001321 Omg -425 40.74 424998356 3. Sa-291 20.01 291.020389 Sa-293 28.71 292.987681 Sa-295 51.28 295.011006 4. Bg-400 29.21 399.979962 Bg-404 40.05 404.001321 Bg-406 30.74 405.998356 5. Lp-372 51.28 372.000809

Convert 89000 g $Pb(NO_{3})_{2}$ to atoms

Given the following reactions and corresponding $\Delta H$ values, find the $\Delta H$ (to the nearest whole \#) for the reaction: $H_{2}SO_{4}(l)\rightarrow SO_{3}(g)+H_{2}O(g)$ $H_{2}S(g)+2O_{2}(g)\rightarrow H_{2}SO_{4}(l)$ $\Delta H=-235kJ$ $H_{2}S(g)+2O_{2}(g)\rightarrow SO_{3}(g)+H_{2}O(l)$ $\Delta H=-207kJ$ $H_{2}O(l)\rightarrow H_{2}O(g)$ $\Delta H=44kJ$ $\square $

Convert $4.68\times 10^{25}$ atoms $PBr_{3}$ to mol

Which of the following best describes a mixture? a material that is made up of many molecules a substance that can be changed into another substance a material that contains two or more substances a substance that has been broken down into Its smallest parts

What is used to of a hope of sixes in a a compound heard on the chermal reme? the periodic table prefixes chemical symbols the IUP AC

40. Using the hyphen form of symbol writing write the name of this atom. ${}_{9}^{19}F^{-1}$

Which of the following will not increase 1 point the rate of a chemical reaction? increasing surface area stirring decreasing the temperature increasing the concentration A __ is a substance that increases the rate of a reaction without being consumed. __ 1 point A(n) __ slows down the rate of a reaction. __ is a substance that 1 point

Use molecular orbital theory to determine the bond order in $H_{2}$ o 2 1 3

What is enthalpy? the heat absorbed or released during a phase change the heat content.of a system at constant pressure the heat absorbed during an endothermic reaction the heat given off during an exothermic reaction

1. What are two ways in which real gases differ from ideal gases? $\square $