Cement mortar is composed of cement, fine aggregate and water, ie, cement + sand + water, and mortar prepared as required. Cement mixed mortar is prepared from cement, fine aggregate, lime and water. The two are different concepts. They are different in name and use.
Generally referred to as 1:3 cement mortar is used with 1 volume of cement and 3 volume of sand, actually ignore the composition of water, generally in the proportion of about 0.6, that is, should be 1:3:0.6, the density of cement mortar is 2000Kg/ M3.
Note: The mortar used in the construction process is generally site-stirred for the convenience of construction. The cement mortar has a 1:3 ratio by weight ratio, and then is converted into a volume ratio according to the capacity of the in-situ mixer or material container; the structure is used in construction. Mortar used more finished mortar, more with mortar strength, such as M5, M7.5, M10 mortar.