Gabriella weighs 450 N. She climbs a flight of stairs to a height of 3 m. It takes her 5 seconds. How much work does Gabriella do when she climbs the stairs?

A.

150 J

B.

270 J

C.

1350 J

D.

2250 J

Where does undigested food goes?

Which physical property of matter can be expressed numerically in SI units?

30 pts! Sodium and water react according to the following equation. If 31.5g of sodium are added to excess water, how many liters of hydrogen gas are formed at STP? Show all work for credit. 2Na+2H2O--> 2NaOH+H2

Cl2 (g) + 2NaBr (aq) 2NaCl (aq) + Br2 (l) The reaction given above is a single replacement reaction because: A. one of the reactants is a gas B. none of the reactants are solids C. chlorine replaces bromine D. the reaction proceeds spontaneously

How many grams of C5H12 must be burned to heat 1.39 kg of water from 21.2 °C to 97.0 °C? Assume that all the heat released during combustion is used to heat the water.

Oil and water a combined to make salad dressing. Physical Change? Chemical Change? Both?

How is water different from most liquids? It expands when it freezes. It contains chemical bonds. It has ionic and covalent bonds. It boils when it is heated.

In the thermal decomposition of copper carbonate, the black solid left behind weights less than the original copper carbonate. Why?

The element Oxygen, O, is an example of which of the following? Question 8 options: A compound B molecule C atom D mixture

For the reaction N2 (g) + 3H2 (g) 2NH3 (g), what will happen if more ammonia gas is added?