Two friends are walking by a cliff face when they notice their voices echo. One friend says to the other "It is 50 metres to that cliff. I can find out the speed of sound using this echo!" The first friend claps and listens for the echo. Then they keep clapping exactly in time with the echoes from the cliff. The second friend times how long it takes for the first friend to clap like this thirty times. It takes them nine seconds to clap thirty times in time with the echoes. Using their experiment and their data, calculate the speed of sound in air.

The speed of sound in air is 333.33 m/s

Explanation:

The parameters given are the time it takes for the sound to male it to the cliff and back = 30 times in 9 seconds

Distance to the cliff = 50 meters

Therefore, the sound covers a distance of 30 × 100 = 3000 meters in 9 seconds

Which give the speed of sound in air using the formula for speed = Distance/Time

Therefore, the speed of sound in air = 3000/9 = 333.33 m/s.

? you expect us to answer this? ? this is your schoolwork, i don't think we can with this, i think it would considering being

alkaline metals are lithium, sodium, rubidium, potassium, cesium and francium.

alkali metals have electronegativity from 0.7 to 1, lowest in periodic table of elements, which means that alkali metals (i group in periodic table) has positive oxidation number in compounds.

electronegativity is a chemical property that describes the tendency of an atom to attract a shared pair of electrons towards itself.

alkaline metals (far left in main group) have lowest ionizations energy and easy remove valence electrons,

for example, potassium is the alkali metal and has a single valence electron in the outer electron shell.

electron configuration of potassium is: ₁₉k 1s²2s²2p⁶3s²3p⁶4s¹.

they can not exist alone in nature, because they are very reactive.