Answers
1. 8 electrons
2. 10 electrons
3. 10 electrons
4. 8 from the oxygen atom and 1 from each of the 2 hydrogen atoms
5. 4 hydrogen bonds
Explanation
The atomic number of oxygen is 8 thus it has a total of 8 electrons. When writing the electron configuration for the oxygen, the first n shell requires two electrons to complete the 1st orbital. The fact that 1s holds a maximum of 2 electrons the next 2 electrons of oxygen goes to 2s orbital. The 2s orbital takes a maximum of two electrons and the remaining 4 electrons occupy the 2p orbital. The configuration formed will be 1s² 2s² 2p4 .The maximum number of electrons in the second shell is 2n²=2×2² =8 from the formula 2n² (the maximum number of electrons in a shell). The total number of electrons in the second shell is 2(in s orbital) +4 (in p orbital) =6.The number of unpaired electrons is 8-6=2
A water molecule has four hydrogen bonds, because it is made up of two hydrogen atoms and an oxygen atom. A water molecule has 10 protons and 10 electrons thus it is neutral. In the water molecule there is formation of covalent bonds where oxygen atom and hydrogen atoms share electrons though the sharing is not equal. In the covalent bond, the oxygen atoms attract electrons more than the hydrogen atoms.
Answer: Ligand gated channel
Explanation:
Ligand gated channel is an essential membrane protein that has pores and allows the passage of specific ions across the plasma membrane when it is activated by a specific chemical . Examples of such ions that pass through Ligand gated channels are Sodium ions, Potassium ions, Calcium ions. Ligand gated channels are found in extensions of the nerve cells.
Answer:
c
Explanation:
when two daughters of cells are produced
Read the excerpt from The Riddle of the Rosetta Stone, by James Cross Giblin.
Another, more complete copy of the same decree that appeared on the Stone was found on a slab at Philae in 1848. Fuller translations of the hieroglyphic text soon followed. A Latin version came out in 1851, a French one in 1867, and an English one in 1871. But many of the hieroglyphs on this slab were missing also, so only a few words and phrases could be added to what was already known from the Rosetta Stone.
Which detail from the excerpt develops the idea that scholars faced many challenges in deciphering the meaning of the decree on the Rosetta Stone?
Answer:
many of the hieroglyphs on this slab were missing
Explanation:
The detail from the excerpt that develops the idea that scholars faced many challenges in deciphering the meaning of the decree on the Rosetta Stone is "many of the hieroglyphs on this slab were missing."
From the available excerpt, it was written that despite many translations of the original text, including the fuller version, the French translation, the Latin version, and the English version, "many of the hieroglyphs on this slab were missing also, so only a few words and phrases could be added to what was already known from the Rosetta Stone."
