Answer:
atoms are too small to be seen under a microscope
Explanation:
scientists have been always making research on atomic structure which cannot be directly looked through a microscope
Titration is used for monitoring the effect of acid rain on drinking water because tiration is<span> very established, reliable, and accurate method. </span><span>A wide variety of reagents can be used, making it very versatile; a lot of different substances can be analysed.</span>
Answer:
The electron geometry, molecular geometry and idealized bond angles for these molecules respectively are:
a. CF4: tetrahedral, tetrahedral and 109.5 degrees
b. NF3 tetrahedral, trigonal pyramidal and 102.5 degrees
c. OF2 tetrahedral, angular and 103 degrees
d. H2S tetrahedral, angular and 92.1 degrees
Explanation:
The electron geometry considers the bound atoms and unbound electron pairs to determine the geometry. The four molecules have four bound atoms and/or unbound electrons pairs, thus they have a tetrahedral geometry. On the other hand, the molecular geometry only considers the position of bound atoms to determine the geometry.
Between H3O and H2O, H2O has a smaller bond angle due to the two unbound electron pairs. The bond angle decrease as the number of unbound electron pairs increases in every molecule.
CO2 and CCl4 are both nonpolar because of the 3D geometry of the molecule. Each individual bond is polar but both molecules have symmetrical geometry so the dipole bonds are canceled.
CH3F is a polar molecule because the dipole between the C-H and C-F bonds are differents thus, besides the symmetrical geometry the dipole bonds are not canceled.
Nucleosomes are the basic packing unit of DNA built from histone proteins around which DNA is coiled. They serve as a scaffold for formation of higher order chromatin structure as well as for a layer of regulatory control of gene expression.
A semiconductor conducts electricity at high temperatures, but not at low temperatures. At high temperatures, metalloids act like metals and conduct electricity.
Explanation:
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