q = (20.5 g)(0.21 J/gC)(230o C- 30o C)
= 861 Joules
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To calculate the number of moles, you need to divide the given mass by the molar mass of helium. The molar mass of helium is approximately 4 g/mol. Therefore, the number of moles in 205g of helium would be 205g / 4g/mol = 51.25 mol.
11 g x 1 mol Si/28.0855 g Si= 0.39 mol Si 205g He x 1mol He/4.002602 g He=51.2 mol He
Helium exists as a monatomic noble gas. Its atomic mass is 4.0 as can be obtained from the periodic table. The amount of helium in a 205g pure sample is given by 205/4.0 which equates to roughly 51 moles.
205g = 7.23oz
205 grams of water is 205 ml
To calculate the number of moles, you need to divide the given mass by the molar mass of helium. The molar mass of helium is approximately 4 g/mol. Therefore, the number of moles in 205g of helium would be 205g / 4g/mol = 51.25 mol.
11 g x 1 mol Si/28.0855 g Si= 0.39 mol Si 205g He x 1mol He/4.002602 g He=51.2 mol He
Helium exists as a monatomic noble gas. Its atomic mass is 4.0 as can be obtained from the periodic table. The amount of helium in a 205g pure sample is given by 205/4.0 which equates to roughly 51 moles.
One tablespoon of solid shortening weighs 13 grams (from label). There are 16 tablespoons in one cup, so 13 x 16 = 208 grams. One-half cup of shortening weighs 104 grams. One-third cup of shortening weighs 69 grams. One-fourth cup of shortening weighs 52 grams. This is the easiest way to weigh shortening. Just be sure to zero out the scale before adding shortening to the cup or bowl.