A 550-L cylinder contains 672.48 g of nitrogen gas at 147 degrees Celsius. The maximum pressure that the cylinder can withstand is 1310 mmHg. How many grams of helium must be added to the cylinder to reach its maximum allowed pressure?

Asolution of sodium hydroxide was titrated against a solution of sulfuric acid. how many moles of sodium hydroxide would react with 1 mole of sulfuric acid?

Determine the reaction and balance the following equations urgent due in the morning

When the chemicals iron sulfide (fes) and hydrochloric acid (hcl) are combined, bubbles appear from the mixture. 1. does the appearance of bubbles indicate a physical or chemical change? 2. why do the bubbles indicate this change? 3. what property is this?