C
The elements are Lithium and Beryllium— just look at the mass number on the periodic table
Answer:
The electron configuration for this atom is Calcium, which has 2 valence electrons.
Explanation:
Following the periodic table and with the electron configuration, you will end up with calcium, which has 2 valence electrons. (Always follow the electron configuration from left to right! It begins at hydrogen, then to helium... and so on.)
1s2 -> He....
2s2 -> Be....
2p6 -> Ne...
3s2 -> Mg...
3p6 -> Ar...
4s2 -> Ca.
moles CO₂ = 5.57.10⁻⁴
<h3>Further explanation
</h3>
A mole is a number of particles(atoms, molecules, ions) in a substance
Can be formulated :

0.7% percent change with 3.5g of plant matter
mass :

moles :

Sulfur smells like rotten egg and is yellow...
Answer:
Explanation:
C = 41.4/12 = 3.43
H = 3.47/1 = 3.47
O = 55.1/16 =3.44
CHO is the skeletal formula (divide each by the lowest number above). The results are close enough to 1 to be 1.
(CHO)_x = 116
C + H + O = 29
(29) _ x = 116
x = 116/29
x = 4
So there area 4 carbons 4 hydrogens and 4 oxygens.
The correct formula is C4H4O4