Answer: A) Sodium Na and Magnesium Mg
Explanation:
In the period table, you can see that Sodium (group 1) has 11 protons, and Magnesium (group 2) has 12 protons. 11+12=23 protons
Answer:
Titration
Explanation:
The best technique which can be used to determine the number of moles of the HCl in the sample is titration.
The given amount of HCl solution must be titrated with known concentration of the base like NaOH.
The volume of NaOH required must be noted also.
According to the reaction,
At equivalence point
Moles of 
= Moles of 
Considering:-
Moles of 
Thus, in this way, moles of HCl can be determined.
The states of matter is solid,liquid and gas & you go from there.
Answer:
2J/g°C
Explanation:
Q = 5000J
Initial temperature (T1) = 20°C
Final temperature (T2) = 70°C
Specific heat capacity (c) = ?
Heat energy (Q) = mc∇T
Q = mc∇T
Q = mc(T2 - T1)
5000 = 50 × c × (70 - 20)
5000 = 50c × 50
5000 = 2500c
c = 5000 / 2500
c = 2J/g°C
The specific heat capacity of the substance is 2J/g°C
Answer:
-1.94 * 10^-18 J
Since the electron moved from a higher to a lower energy level (n = 3 → n = 1) it is an emission.
Explanation:
From Rydberg equation;
E = -RH(1/n^2final - 1/n^2initial)
For a transition from n = 3 → n = 1
RH = 2.18 * 10^-18 J
E = -(2.18 * 10^-18) (1/1^2 - (1/3^2)
E = -(2.18 * 10^-18) (1-1/9)
E= -(2.18 * 10^-18) (8/9)
E = -1.94 * 10^-18 J
