The mass of 1 mole of an element is its atomic weight on the Periodic Table in grams.
1g = 1000mg
The mass of 1 mole of Kr = 83.80g Kr
Convert mg Kr to g Kr.
398mg Kr x (1g/1000mg) = 0.398g Kr
Convert g Kr to mol Kr.
0.398g Kr x (1mol Kr/83.80g Kr) = 4.75x10-3mol Kr
7.98 moles of Kr have 668,708 g.
3.99 moles × 83.8 grams/mol = 334.362 grams
First we need the moles of krypton gas. Monoatomic gas.0.405 grams Kr (1 mole Kr/83.80 grams)= 0.004833 moles krypton gas======================Now the ideal gas equation.PV = nRT(1 atm)(X volume) = (0.004833 moles Kr)(0.08206 L*atm/mol*K)(298.15 K)= 0.118 Liters of krypton gas--------------------------------------
Use PV = nRT and solve for n. Thus, n = PV/RT = (0.918atm)(0.555L)/(0.0821 L-atm/deg-mole)(298)n = 0.0208 moles (0.021 moles to 2 sig figs)
The mass in grams of KBr contained in 2.50 moles of the compound is 2.5 times the sum of the gram atomic masses of hydrogen and bromine, or 2.50(1.008 + 79.904) or 202 grams, to the justified number of significant digits.
0.377 grams of Kr is equal to 0,0045 moles.
The mass of 1 mole of an element is its atomic weight on the Periodic Table in grams.1g = 1000mgThe mass of 1 mole of Kr = 83.80g KrConvert mg Kr to g Kr.398mg Kr x (1g/1000mg) = 0.398g KrConvert g Kr to mol Kr.0.398g Kr x (1mol Kr/83.80g Kr) = 4.75x10-3mol Kr
7.98 moles of Kr have 668,708 g.
7.98 moles of Kr have 668,708 g.
3,99 moles of Kr have 334,35 g.
3,99 moles of Kr is equal to 334,354 g.
4.56 moles Kr x 83.798 g/mole = 382.119 grams = 382 grams (to 3 significant figures)NOTE: You should not use more than 3 significant figures since 4.56 moles limits the precision. Thus the answers of 381.66g and 382.1188 g are incorrect.
The number of atoms is 15,11.10EX23.
1 mole Kr = 6.022 x 1023 atoms 1.7 x 1025 Kr atoms x (1 mole Kr)/(6.022 x 1023 Kr atoms) = 28 moles Kr (rounded to two sig figs)
Just multiply the moles of Kr by Avogadro's number. Formal set up.1.29 moles Kr (6.022 X 1023/1 mole Kr)= 7.77 X 1023 atoms of krypton====================
Given the balanced equation Kr + 3F2 --> KrF6 In order to find how many moles of F2 are needed to produce 3.0 moles of KrF6, we must convert from moles to moles (mol --> mol conversion). 3.0 mol KrF6 * 3 molecules F2 = 9.0 mol F2 --------- 1 molecule F2
3.99 moles × 83.8 grams/mol = 334.362 grams