Answer:
option A is correct ( sodium, calcium and barium)
Explanation:
Given compounds:
Sodium chloride , calcium sulfide, barium oxide
We know that metals form positive ions. In order to solve the problem we must identify the metals from given compounds.
Na⁺Cl⁻
Ca²⁺S²⁻
Ba²⁺O²⁻
We can see that sodium, calcium and barium contain positive charges.
Thus option A is correct.
Because sodium have one valance electron. When it combine with chlorine sodium lose its one electron to complete the octet and chlorine accept it to complete its octet. Thus sodium form positive ion and chlorine form negative ion.
Similarly barium and calcium are present in group 2. Both have two valance electron. When they lose them cation are formed.
Other option are incorrect because,
Option B have sulfur and oxygen which are anion.
Option C have chlorine which is also anion
Option D have chlorine, sulfur and oxygen that are anions.
Cardenolides, with the chemical formula CH₁₈C₂₀H₁₅CHCO₂ have (D) 23 carbon atoms, 34 hydrogen atoms, and 2 oxygen atoms.
Milkweed contains a poison known as cardenolides. The chemical formula for cardenolides CH₁₈C₂₀H₁₅CHCO₂.
The subscripts in the formula represent the atomicities, that is the number of atoms of each element in each part of the formula.
We can calculate the total number of atoms of each element by adding its atomicities.
<h3>Carbon atoms</h3>
<h3>Hydrogen atoms</h3>
<h3>Oxygen atoms</h3>
Cardenolides, with the chemical formula CH₁₈C₂₀H₁₅CHCO₂ have (D) 23 carbon atoms, 34 hydrogen atoms, and 2 oxygen atoms
Learn more: brainly.com/question/13348838
1) Compund Ir (x) O(y)
2) Mass of iridium = mass of crucible and iridium - mass of crucible = 39.52 g - 38.26 g = 1.26 g
3) Mass of iridium oxide = mass of crucible and iridium oxide - mass of crucible = 39.73g - 38.26g = 1.47g
4) Mass of oxygen = mass of iridum oxide - mass of iridium = 1.47g - 1.26g = 0.21g
5) Convert grams to moles
moles of iridium = mass of iridium / molar mass of iridium = 1.26 g / 192.17 g/mol = 0.00656 moles
moles of oxygen = mass of oxygen / molar mass of oxygen = 0.21 g / 15.999 g/mol = 0.0131
6) Find the proportion of moles
Divide by the least of the number of moles, i.e. 0.00656
Ir: 0.00656 / 0.00656 = 1
O: 0.0131 / 0.00656 = 2
=> Empirical formula = Ir O2 (where 2 is the superscript for O)
Answer: Ir O2
Answer:
not 100% but i think its 1.57x10^20
Explanation:
5.25x10^-4g / 2.016g
2.60x10^-4 x 6.022x10^23= 1.56x10^20 molecules
