Answer:
15.95
Explanation:
This question is a modification of the calculation of the empirical formula of a compound given its percent composition and atomic weights of the elements in the compound.
Here we are given the formula and the percent composition, so we know that there are 4 atoms of E per 2 atoms of N so lets solve using the information given.
In 100 grams of the binary compound we have
30.46 g N
69.54 g E
The number of moles is the mass divided by atomic weight:
mol N = 30.46 g / A.W N = 30.46 g / 14.00 g/mol = 2.18 mol N
mol E = 65.54 g / A.W E
Thus,
4 mol E/ 2 mol N = ( 69.54 g/ A.W E ) / 2.18
2 A.E = 65.54 g / 2.18 ⇒ A.W E = 69.54 g / ( 2 x 2.18 ) = 15.94 g
So the A.W is 15.94 g/mol which is close the atomic weight of O.
It’s called an isotope which is an atom with the same number of protons but a different number of neutrons
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
The energy required to raise the temperature of 3 kg of iron from 20° C to 25°C is 6,750 J( Option B)
<u>Explanation:</u>
Given:
Specific Heat capacity of Iron= 0.450 J/ g °C
To Find:
Required Energy to raise the Temperature
Formula:
Amount of energy required is given by the formula,
Q = mC (ΔT)
Solution:
M = mass of the iron in g
So 3 kg = 3000 g
C = specific heat of iron = 0.450 J/ g °C [ from the given table]
ΔT = change in temperature = 25° C - 20°C = 5°C
Plugin the values, we will get,
Q = 3000 g × 0.450 J/ g °C × 5°C
= 6,750 J
So the energy required is 6,750 J.
Answer:
B
B
A
C
D
Explanation:
I think dont take my word for though
