Please, I need help with this badly: Substance A has a normal melting point of -25.0 °C, an enthalpy of fusion of 1200 J g'; specific
heat for the solid is 3.00 Jg'c and the liquid is 6.20 J g''C'' Determine the heat needed to
change 150 grams of A from a solid at - 40.0 °C to a liquid at +70.0°c. Draw the diagram to
illustrate the process that is occurring.

Explain the relationship between forward and backward reactions in equilibrium, and predict how changing the amount of a reactant (creating a tension) will affect that relationship.

What happened to the amount of carbon dioxide in the atmosphere from 2010–2017?

Cryolite, na3alf6(s), an ore used in the production of aluminum, can be synthesized using aluminum oxide. start this question by first balance the chemical equation.1.) balance the equation: - alo3(s)+naoh(l)+hf(> na3alf6+h2o(g). 2.) if 17.5 kilograms of al2o3(s), 51.4 kilograms of naoh(l), and 51.4 kilograms of hf(g) react completely, how many kilograms of cryolite will be produced? 3.)which reactants will be in excess, (al2o3, naoh, or hf) 4.)what is the total mass of the excess reactants left over after the reaction is complete in kg?