What is the mass of an element with 78 protons and 78 neutrons

What pressure will be exerted by 0.675 moles of a gas at 25*c if it is in a 0.750-l container?

Sarah wants to know where in her garden chamomile would grow the best. she thinks chamomile will grow best in the corner of the garden that gets the most sunlight. to test her hypothesis, she decides to plant several groups of chamomile in her garden as an experiment. which of the following variables will sarah need to measure to know which group of plants grew best? a. the location of the plants b. the type of plants c. the height of the plants d. the amount of water she gives the plants

What’s the percent by mass of carbon in c10h14n2