Answer:
a. Be and Mg
Explanation:
Be (beryllium) and Mg (magnesium) are both found in the alkaline earth metals family (group 2) on the periodic table. Elements in the same family or group have similar properties,
Ca and Br are in groups 2 and 17
Cl and Ar are in groups 17 and 18
Na and P are in groups 1 and 15
The initial mass of sodium hydroxide is 3.3 g (answer C)
<u><em>calculation</em></u>
Step 1 : find the moles of iron (ii) hydroxide ( Fe(OH)₂
moles = mass÷ molar mass
from periodic table the molar mass of Fe(OH)₂ = 56 + [16 +1]2 = 90 g/mol
moles is therefore = 3.70 g÷ 90 g/mol = 0.041 moles
Step 2: use the mole ratio to calculate the moles of sodium hydroxide (NaOH)
from given equation NaOH : Fe(OH)₂ is 2 :1
therefore the moles of NaOH = 0.041 x 2 = 0.082 moles
Step 3: find mass of NaOH
mass = moles x molar mass
from the periodic table the molar mass of NaOH = 23 +16 +1 = 40 g/mol
mass = 0.082 moles x 40 g/mol = 3.3 g ( answer C)
Relative dating is the process of determining whether an object or event is older or younger than other objects or events. Absolute dating is d<span>etermining the age of an event or object in years. From absolute dating, the real age of the object is obtained which is not present for relative dating. Hope this helps.</span>
Answer:
Solid metal
Explanation:
The reduced form of metal ions is the metal in elemental state (simple substance). So, if you have a solution with metal ions and they are reduced, you probably will see the deposition of the metal. For example: if you have a solution with sodium ions (Na⁺), and the ions are then reduced, you will see the aparition of a solid phase of metallic sodium (Na(s)), according to the following half-reaction:
Na⁺ + e- → Na(s)
