What is the balanced equation for H3PO4=H4P2O7+H2O

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

Melting and boiling are endothermic processes. this means that these processes absorb energy from their surroundings in order to occur. use this information and the data you collected in the phase change gizmo to describe what happens to the temperature of water when you boil it, then explain why this result occurs.

How are isotopes of the same chemical element alike? how are they different?