Answer:
B
Explanation:
bonding is a process of two different atoms sharing electrons for stability and these electrons are attracted by one atom losing it's electrons to another
Given that,
Work done by the system = 125 J
Energy released when it cools down = 438 J
To find,
The change in internal energy.
Solution,
As heat is released by the system, Q = -438 J
Work done by the system, W = -125 J
Using the first law of thermodynamics. The change in internal energy is given by :
So, the change in internal energy is 563 J.
Answer:
c) (12×0.9889) + (13×0.01108)
Explanation:
Given data:
Percentage of C-12 = 98.89%
Percentage of C-13 = 1.108%
Atomic mass = ?
Solution:
98.89/100 = 0.9889
1.108/ 100 = 0.01108
Atomic mass = (12×0.9889) + (13×0.01108)
Atomic mass = (11.8668 + 0.144034)
Atomic mass = 12.01084
Answer:
0.12M
Explanation:
A balanced equation for the reaction will go a great deal in obtaining our desired result. So, let us write a balanced equation for the reaction
HCl + NaOH —> NaCl + H2O
From the above equation,
nA (mole of the acid) = 1
nB (mole of the base) = 1
Data obtained from the question include:
Vb (volume of the base) = 30mL
Mb (Molarity of the base) = 0.1M
Va (volume of the acid) = 25mL
Ma (Molarity of the acid) =?
The molarity of the acid can be obtained as follow:
MaVa/MbVb = nA/nB
Ma x 25/ 0.1 x 30 = 1
Cross multiply to express in linear form
Ma x 25 = 0.1 x 30
Divide both side by 25
Ma = (0.1 x 30) / 25
Ma = 0.12M
The molarity of the acid is 0.12M
Using the periodic table, find the molar mass of each compound in CaCO3
CA = 40
C = 12
O = 16
Molecular Mass = 40 + 12 + (16 x3) = 100 grams.
Number of moles = given mass / molecular mass
Number of moles = 240 g / 100g = 2.4 moles
