Answer: With atomic number 20, calcium atoms have 20 positive protons, and the ion has only 18 electrons, which means the net charge is +2. Calcium ions are essential for muscle contractions, nerve impulses, and bone maintenance.
:
Jenny puts the ph paper and lines it up PH SCALE to find how strong the solution.
Molar mass of Calcium ( Ca ) = 40.078 g/mol
Number of moles in 9.8 grams :
1 mole Ca -----------> 40.078 g
mole Ca -------------> 9.8 g
moles Ca = 9.8 / 40.078
moles Ca = 0.2445 moles
number of molecules:
1 mole ----------------> 6.02x10²³ molecules
0.2445 moles --------> ?
= 0.2445 * 6.02x10²³
= 1.47x10²³ molecules
hope this helps!.
The chemical formula : X₃Y₂
<h3>Further explanation </h3>
The noble gas element is a stable class of elements. The noble gas element is monatomic. Stability of noble gases is caused by an electron configuration that has a stable configuration of 8 (has 8 valence electrons) except He with a duplet configuration (has 2 valence electrons)
Other elements that do not yet have electron configurations such as noble gases will try to achieve their stability by forming bonds between elements.
This is generally called the octet rule
X has 2 valence electrons.to achieve stability, element X will release 2 electrons to form X²⁺
Y has 5 valence electrons, to achieve stability, the element Y will attract/ add electrons to form Y³⁻
The two compounds will form a compound with the charges crossed : X₃Y₂
The number of grams is 10