Aballoon is filled with 35.0 l of helium in the morning when the temperature is 20.00 celsius by noon the temperature has risen to 45.00 celsius what is the new volume of the balloon

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How many grams of mgbr2 are needed to produce 75g or metal?

In 1901, thomas edison invented the nickel-iron battery. the following reaction takes place in the battery. fe(s) + 2 nio(oh)(s) + 2 h2o(l) fe(oh)2(s) + 2 ni(oh)2(aq) how many mole of fe(oh)2, is produced when 4.20 mol fe and 6.70 mol nio(oh) react?