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Would freezing liquid mercury be considered a physical or chemical change?. physical. Would dissolving sodium chloride in water be considered a physical or chemical change?. physical. What are the two categories of pure substances?. Elements and compounds.
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Would freezing liquid mercury be considered a physical or chemical change?
Would dissolving sodium chloride in water be considered a physical or chemical change?
How can an element be further separated? By ordinary physical means; By ordinary chemical means; Or it cannot be further separated by ordinary physical or chemical means.
At one point in the school year, our room was a comfortable 85°F. Is this observation qualitative or quantitative?
A group of measurements that closely agree with one another but are far from the “true” value are said to be…
How many sig figs are in the following measurement: 0.0390060
Object A has a mass of 15.2 g and a volume of 3.6 mL. Object B has a volume of 4.1 mL and a mass of 16.8 g. Which will sink first in water?
You are in the lab and need to mix hydrochloric acid and water. In what order should you do this?
Which subatomic particle has a mass so small that it is considered negligible when finding mass number?
An unknown element has 38 protons, 36 electrons, and 50 neutrons. Identify the element.
Isotopes occur when atoms of the same element have different mass numbers. Therefore, an isotope has the same # of ______, but a different # of ______.
Same = protons Different = neutrons
An atom has an atomic # of 31 and a mass # of 70. How many protons, electrons, and neutrons does the atom have?
Protons = 31 Electrons = 31 Neutrons = 39
How many electrons can be held in each energy level (n=1, n=2, n=3, & n= 4) of the atom?
n = 1 2e- (s) n = 2 8e- (s, p) n = 3 18e- (s, p, d) n = 4 32e- (s, p, d, f)
Calculate the wavelength of a photon with an energy of 1.66x10-20 kJ.
E = 1.66x10-17 J V = 2.5 x1016 Hz Wavelength = 1.2 x10-8 m
What type of elements tend to form covalent/molecular bonds?
Which molecule is nonpolar: BH3 or PH3?
According to VSEPR theory, what is the molecular geometry of the compound chlorine pentafluoride ?
What type of bond is likely to form between two atoms with the same electronegativity value?
When comparing single, double and triple covalent bonds, a single covalent bond has the ____ bond length and the _____ bond enthalpy.
Single Covalent Bond Longest – bond length Lowest/weakest – bond enthalpy