Answer:
The specific heat of the alloy 
Explanation:
Mass of an alloy
= 25 gm
Initial temperature
= 100°c = 373 K
Mass of water
= 90 gm
Initial temperature of water
= 25.32 °c = 298.32 K
Final temperature
= 27.18 °c = 300.18 K
From energy balance equation
Heat lost by alloy = Heat gain by water
[
-
] =
(
-
)
25 ×
× ( 373 - 300.18 ) = 90 × 4.2 (300.18 - 298.32)

This is the specific heat of the alloy.
<h3><u>Answer;</u></h3>
2, Blank, 2 ;
<h3><u>Explanation;</u></h3>
The balanced chemical equation would be;
2 CO + O2 → 2 CO2
Balancing a chemical equation ensures that the number of atoms of each element are equal on both the reactants side and the products side. This ensures that the law of conservation of mass is obeyed in chemical reactions.
Answer:

Explanation:
Alkaline earth metals are in group 2. The number of valence electrons of elements in group 2 is 2.
Answer:
Percent yield: 78.2%
Explanation:
Based on the reaction:
4Al + 3O₂ → 2Al₂O₃
<em>4 moles of Al produce 2 moles of Al₂O₃</em>
<em />
To find percent yield we need to find theoretical yield (Assuming a yield of 100%) and using:
(Actual yield (6.8g) / Theoretical yield) × 100
Moles of 4.6g of Al (Molar mass: 26.98g/mol) are:
4.6g Al × (1mol / 26.98g) = 0.1705 moles of Al.
As 4 moles of Al produce 2 moles of Al₂O₃, theoretical moles of Al₂O₃ obtained from 0.1705 moles of Al are:
0.17505 moles Al × (2 moles Al₂O₃ / 4 moles Al) = <em>0.0852 moles of Al₂O₃</em>,
In grams (Molar mass Al₂O₃ = 101.96g/mol):
0.0852 moles of Al₂O₃ × (101.96g / mol) =
<h3>8.7g of Al₂O₃ can be produced (Theoretical yield)</h3>
Thus, Percent yield is:
(6.8g / 8.7g) × 100 =
<h3>
78.2% </h3>