1. moving from left to right across a row of the periodic table, which of the following values increases by exactly one from element to element? (1 point) isotope number atomic number atomic mass unit mass number 2. the atomic mass of an element is (1 point) the sum of the protons and neutrons in one atom of the element. twice the number of protons in one atom of the element. a ratio based on the mass of a carbon-12 atom. a weighted average of the masses of an element’s isotopes. 3. which general statement does not apply to metals? (1 point) most metals are ductile. most metals are malleable. most metals are brittle. most metals are good conductors of electric current. 4. group 7a of the periodic table contains the (1 point) most reactive nonmetals. most reactive metals. least reactive nonmetals. least reactive metals. 5. the unit for atomic mass is (1 point) gram. amu. pound. none of the above

Air is held within a frictionless piston-cylinder container, which is oriented vertically. the mass of the piston is 0.45 kg and the cross-sectional area is 0.0030 m2. initially (state 1) the pressure of the gas is sufficient to support the weight of the piston as well as the force exerted by the atmospheric pressure ( 101.32 kpa). the volume occupied by the air within the cylinder in state 1 is 1.00 liter. one end of a spring (with spring constant k = 1000 n/m) is attached to the top of the piston, while the other end of the spring is attached to a stage that can move vertically. initially the spring is undeflected and therefore exerts no force. then the stage is then moved quasistatically downward a distance of 10.0 cm, at which point the system reaches state 2. the piston-cylinder is not insulated; rather it remains in diathermal contact with the surroundings, which are at a constant temperature of 300 k. what is the change of pressure within the container?

An object has a weight of 500 on earth what is the mass of this object

Which is not an example of how an object gains elastic potential energy by stretching? a. jumping on a pogo stick b. pulling on a rubber band c. jumping on a trampoline