Which statement about the physical change of liquid water boiling into steam is true? The heat added represents an energy change.
The action cannot be reversed.
The steam cannot conserve mass.
The weight lost represents a mass change.

Astudent made the lewis dot diagram of a compound shown. what is the error in the lewis dot diagram? a)an o atom should transfer all of its six electrons to mg because the formula is mgo b) both electrons of mg should be transferred to one o adam because the formula is mgo c) the electrons should be transferred from each o add him to capital mg because mg has fewer electrons d) the number of dots around mg should be four because it has to transfer two electrons to each o

Chromosome 17 is made of over million base pairs.

Choose all the answers that apply. fluorine (f) has an atomic number of 9 and an atomic weight of 18.99. fluorine has a. 9 protons b. 10 neutrons c. 18 electrons d. an atomic mass of 19 e. at least one isotope