Which of these is an example of a physical change?

A) iron melting

B) steel rusting

C) paper burning

D) wood decaying

A salt sample is placed into some water and nearly all of it dissolve without stirring and heating. the resulting solution is

There are two main ways that minerals are classified. Which identifies those two main ways? A. country of origin and chemical makeup B. chemical makeup and use C. crystal structure and economic value D. use and economic value

A 0.642g sample of an unknown gas was collected over water at 25.0°C and 1.04 atm. The collection cylinder contained 151.3 mL of gas after the sample was released. Find the molar mass of the unknown gas.

Find the molality of the solution if 2.5 moles of CaBr2 are dissolved in 5 kg of water. -500 m -5 x 10-4 m -0.5 m -2 m

Which unit is commonly used for measuring pressure? A. m3 B. bar C. N/m3 D. Celsius

Which of the following statements is not considered weather? The wind is blowing 20 miles per hour right now in Kansas. It is raining in Seattle. It is usually humid in Florida. It is snowing in Colorado.

A nickel atom (Ni) has a mass numbet of 61. how many neutrons does the atom have

Select the more electronegative element in each pair. a. Cl or Fb. Se or Oc. N or Asd. Na or Mg

Find the molar mass of potassium dichromate, K2Cr2O7

Zn (s) + cu2 + (aq) →zn2 + (aq) + cu (s). part a under standard conditions, what is the maximum electrical work, in joules, that the cell can accomplish if 51.0 g of copper is plated out?