ΔT = 21º C - 20 ºC => 1 º C
Q = m x C x ΔT
Q = 10 x 0.09 x 1
Q = 0.9 Cal
hope this helps!
Archeology? maybe im not too sure
A becuase that is the one that is also b becuase a and c
Answer:
Explanation:
A physical change is a change in which the physical properties of matter are altered. These are properties are the forms and state.
Most physical changes are easily reversible and are pure state changes.
They do not lead to the production of new compounds.
They involve no mass change and requires little to no energy.
Examples are melting, boiling, freezing, sublimation e.t.c
Covalent bond is the term that is being used to describe the bonds in the compounds that are created due to the sharing of one or more electrons. One of the best example of the simplest covalent bond is the bond that is being created when two isolated hydrogen atoms come together to form an H2 molecule. An isolated hydrogen atom has one proton and electron being combined by the force of attraction from the opposite-charged articles. When a pair of isolated hydrogen atom combines, two forces of attraction are created coming from each of the isolated hydrogen atom.