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.
Answer:
A group of cells ready to form roots a stem and the first leaves
I think the correct answer would be HCl + NaHCO3 -> NaCl + H2O + CO2, 2HCl + CaCO3 -> CaCl2 + CO2 + H2O, 2HCl + Mg(OH)2 -> MgCl2 + 2H2O. Hydrochloic acid would react with the basic substances in the stomach which are magnesium hydroxide, sodium bicarbonate and <span>calcium carbonate.</span>
It would be MnSO4
The (II) lets you know it’s the form with a 2+ charge and Sulfate has a 2- charge
These will cancel out making it plain MnSO4
If it was manganese (iii) sulfide the answer would be Mn2(SO4)3
The variables in the ideal gas constant has V as the unit of liters and T has the unit of Kelvin. Thus, option C is correct.
The gas constant in an ideal gas equation has been the value of the energy absorbed by 1 mole of an ideal gas at standard temperature and pressure.
The value of R has been dependent on the units of volume, temperature and pressure of the ideal gas.
The given value of R has been 0.0821 L.atm/mol.K
The unit in gas constant has been L (Liter) for volume (V).
The unit of pressure (P) has been atm.
The unit of temperature (T) has been Kelvin (K).
Thus the gas law constant used by student has V has the unit of liters and T has the unit of Kelvin. Thus, option C is correct.
For more information about the gas constant, refer to the link:
brainly.com/question/24814070
