Which equations are balanced? Check all that apply.

Mg3N2 + H2O → 3MgO + 2NH3

C3H8 + 5O2 → 4H2O + 3CO2

Zn + 2HCl → ZnCl2 + H2

3Ca (OH) 2 + 2H3PO4 → Ca3 (PO4) 2 + 6H2O

3H2SO4 + 2Fe → Fe2 (SO4) 3 + H2

4Al + 3O2 → 2Al2O3

Explain why a soda can feel cold when you take it out of the refrigerator.

Four samples, each having a void ratio of 0.76 and a specific gravity of 2.74, have degrees of saturation (S) of 85, 90, 95, and 100%. Determine the total (wet/moist) unit weight (γt) in pcf for each of the four samples.

A baseball player throws a ball in the air with an initial speed of 50 m/s at an angle of 30 degrees above the horizontal. What is the vertical component of the ball’s initial velocity assuming up is the positive direction?

Identify the main renewable energy resources

Does an object that feels cold to the touch contain thermal energy Explain your answer

Which best blocks X-ray particles and can therefore be observed more closely through the use of this technology?

A light ray travels inside a horizontal plate of glass, striking its upper surface at an angle of incidence of 50°. This ray is totally internally reflected at the glass-air boundary. A liquid is then poured on top of the glass.

A stationary object has no forces acting on it. True False

April swims 50 m north and then turns and swims 20 m back to the south. What is her velocity if it takes her 60 seconds?

What happens to the mass of an object when it is cooled?