Answer:
A pure substance is a form of matter that has a constant composition and properties that are constant throughout the sample. Mixtures are physical combinations of two or more elements and/or compounds.
The empirical formula is CH2O bc you divide the percent and the mass of the element, Carbon 40/12.01=3.33, Hydrogen 6.7/1.01=6.63, Oxygen 53.3/16.00=3.33, then divide the lowest number which is 3.33 to all Carbon 3.33/3.33=1, Hydrogen 6.63/3.33=1.99 but rounds to 2, Oxygen 3.33/3.33=1
Answer:
BF 3
Explanation:
The geometry of the BF 3 molecule is called trigonal planar The fluorine atoms are positioned at the vertices of an equilateral triangle. The F-B-F angle is 120° and all four atoms lie in the same plane.
Pahoehoe and Aa are two types of lava
Answer:
1.31x10¹¹ g/cm³
Explanation:
The mass of the proton is equal to the mass of the neutron, which is 1.67x10⁻²⁴ g, so the mass of the alpha particle is 4*1.67x10⁻²⁴ = 6.68x10⁻²⁴ g.
1 fm = 1.0x10⁻²³ cm, thus the radius of the alpha particle is 2.3x10⁻¹² cm. If the particle is a sphere, the volume of it is:
V = (4/3)*π*r³, where r is the radius, so:
V = (4/3)*π*(2.3x10⁻¹²)³
V = 5.1x10⁻³⁵ cm³
The density of the particle is the how mass exists per unit of volume, so, it's the mass divided by the volume:
d = 6.68x10⁻²⁴/5.1x10⁻³⁵
d = 1.31x10¹¹ g/cm³