3 Lithium, sodium and potassium are in Group I of the Periodic Table. a The equation for the reaction of lithium with water is
2Li + 2H,
02LiOH+H,
i Write a word equation for this reaction.
ii Sodium reacts with water in a similar way to lithium.
Write a symbol equation for the reaction of sodium with water.
b Describe the reactions of lithium, sodium and potassium with water. In your description, write about:
the difference in the reactivity of the metals
the observations you would make when these metals react with water.

Considering only the earth's rotation, determine how much later the asteroid would have had to arrive to put the explosion above helsinki at longitude 25˚ e? this would have obliterated the city.

Which of the following situations is impossible? a) an object has velocity directed east and acceleration directed east. b) an object has zero velocity but non-zero acceleration. c) an object has constant non-zero velocity and changing acceleration. d) an object has velocity directed east and acceleration directed west. e) an object has constant non-zero acceleration and changing velocity.

Awater balloon launcher uses an elastic band with a spring constant of 115 n/m to use thee launcher you stretch thee band back with a balloon n it the water balloons have a mass of 1.3 kg a) if you stretch the band by 0.8 m, what elastic force will the band exert? b) with the band stretched 0.8 m, how much elastic potential energy is stored in the spring? c) if you release the band, it pushes forward. what is the kinetic energy of the balloon when it reaches the natural length of the band? d) what is the speed of the balloon when it reaches the natural length of the band?