3. Which element have only one valence electron? (10 puntos)
Be
S
Kr
Cs

15 points

If the root word engage means “to connect with something,” what does the word disengage mean in the following sentence? he disengaged the gears by stepping on the clutch pedal.a.added more engine powerb.activated a connection to the pedalc.stalled the engined.released a connection to the pedal

The is a particle with one unit of positive charge a. proton b. positron c. electron d. nucleus awnser quick it is a important science test!

Calculate the number of molecules present in 0.750 mol of mgo.