Answer: temperature and salinity.
Explanation:
The objects which cannot be observed in detail without a microscope
include the following:
<h3>What is a Microscope?</h3>
A microscope is an instrument which is used to view smaller objects such as
microbe,cells, tissues etc. This instrument is used in viewing the different
cells found in the body as they can't be seen with the eye.
The remaining options which can be seen with the eyes don't require
the use of microscopes.
Read more about Microscope here brainly.com/question/25268499
2 valence electrons
Explanation:
Most transition metals have 2 valence electrons. Valence electrons are the sum total of all the electrons in the highest energy level (principal quantum number n). Most transition metals have an electron configuration that is ns2(n−1)d , so those ns2 electrons are the valence electrons.
The balanced chemical reaction is:
<span>2Na + 2H2O → 2NaOH + H2
</span><span>
We first use the amount of hydrogen gas to be produced and the molar mass of the hydrogen gas to determine the amount in moles to be produced. Then, we use the relation from the reaction to relate H2 to Na.
53.2 g H2 ( 1 mol / 2.02 g ) ( 2 mol Na / 1 mol H2 ) ( 22.99 g / 1 mol ) = 1210.96 g Na
1210.96 g Na ( 1 mL / 0.97 g ) = 1248.41 mL Na needed</span>
