Gas pressure is measured in mmHg with a barometer
Answer:
Since the middle of the 19th century, minerals have been classified on the basis of their chemical composition. Under this scheme, they are divided into classes according to their dominant anion or anionic group (e.g., halides, oxides, and sulfides).
Explanation:
Apart from the free gases in Earth’s atmosphere, some 20 elements occur in nature in a pure (i.e., uncombined) or nearly pure form. Known as the native elements, they are partitioned into three families: metals, semimetals, and nonmetals. The most common native metals, which are characterized by simple crystal structures, make up three groups: the gold group, consisting of gold, silver, copper, and lead; the platinum group, composed of platinum, palladium, iridium, and osmium; and the iron group, containing iron and nickel-iron. Mercury, tantalum, tin, and zinc are other metals that have been found in the native state.
Answer:

Explanation:
Given that:
The energy of the photon = 2.3 eV
Energy in eV can be converted to energy in J as:
1 eV = 1.60 × 10⁻¹⁹ J
So, Energy = 
Considering

Where,
h is Plank's constant having value 
c is the speed of light having value 
is the wavelength of the light being bombarded
Thus,




Also,
1 m = 10⁻⁹ nm
So,

Answer:
Ice is less dense than water because of the way it forms a hexagonal crystalline structure. Each water molecule consists of two hydrogen atoms bonded to the bottom of an oxygen atom. ... In the winter, temperatures in a lake get close enough to freezing that the colder water is less dense and floats to the top
Explanation:
Answer:
the answer is 119.0023 grams