3. According to the conservation of matter the mass of the products fror a chemical reaction
the mass of reactants.
a. is always greater than
b. is always less than
c. is always same as
d. may be more or less than

we can conclude that the melting point of table salt is above room temperature (it's actually 801 deg c). the melting point of mercury must be below room temperature (- 39 deg c).

i would say b

explanation:

but i think i would need more information than that

rosa was looking for patterns to predict the products of chemical reactions. she recorded three similar decomposition reactions in the table.she should record 2licl + 3o2.

in the last row of the table. it is the thermal decomposition of chlorate lithium, hence, she should record these products as: lithium chloride ( 2licl ) and oxygen ( 3o2 )   2 > 2 licl + 3o2.