Why substance dissolve?

How many protons and neutrons are in the following isotope radium-226

Which of the following will increase the strength of a copper electromagnet A. Adding more loops to the wire B. Using DC current (like from a battery) instead of AC current (like from the wall) C. Increasing the current D.

A 5.5 g sample of a substance contains only carbon and oxygen. Carbon makes up 35% of the mass of the substance. The rest is made of oxygen. You are asked to determine the mass of oxygen in the sample.

What are two of the characteristics of water that make it so important in living organisms?

Reaction rate depends on how many molecules are coming into contact with each other with enough energy to react. Increasing the concentration of reactants will increase A. how often they come in contact B. the amount of energy they have C.

The advantage of excreting nitrogenous wastes as urea rather than as ammonia is that

Which molecule is a dipole? CH4 N2 CCl4 NO2 BF3

Calculate the enthalpy of the formation of butane, C4H10, using the balanced chemical equation and the standard value below: 4C (s) + 5H2 (g) = > C4H10 (g) Standard enthalpy of formation values: (Delta Triangle) H^0 of C (s) = - 393.

What volume of lead (of density 11.3 g/cm3) has the same mass as 330 cm3 of a piece of redwood (of density 0.38 g/cm3) ?

What electrically neutral atom will have an electron configuration of 1 s 22 s 22 p 4? Use a periodic table. Question 5 options: nitrogen (N) oxygen (O) carbon (C) fluorine (F)