4.3 moles of Ra(OH)2 to grams

Three cards with holes are arranged in a straight line. a light is shined through the first card’s hole and travels through all three cards. what does this tell you about light rays? a) that light is reflected b) that light is refractive c) that light travels in a straight line d) that light does not travel in a straight line

The vapor pressure of ethanol is 1.00 × 102 mmhg at 34.90°c. what is its vapor pressure at 61.61°c? (δhvap for ethanol is 39.3 kj/mol.)

If you need to add 27.50ml of a solution, which piece of glassware would you use to deliver this volume and explain how you would determine if the 27.50 ml was measured?