Answer:
m= 29.645 g
Explanation:
Density:
Density is equal to the mass of substance divided by its volume.
Units:
SI unit of density is Kg/m3.
Other units are given below,
g/cm3, g/mL , kg/L
Formula:
D=m/v
D= density
m=mass
V=volume
Symbol:
The symbol used for density is called rho. It is represented by ρ. However letter D can also be used to represent the density.
Given data:
density of wood = 0.77 g/cm³
volume= 38.5 cm³
mass= ?
Solution:
d= m/v
m= d × v
m= 0.77 g/cm³× 38.5 cm³
m= 29.645 g
1 mol = 6.023x10^23 number of molecules (Avogadro's number)
1 : 6.023x10^23
X : 4.91x10^22
(6.023x10^23)X = 4.91x10^22
X = 4.91x10^22/6.023x10^23
X = 0.082 Moles
Answer:
H2C2O4.2H20 → CO2 + CO + H2O
Explanation:
Oxalic acid crystals are nothing but dehydrated oxalic acid (H2C2O4 . 2H2O).
On heating, the water of crystallization is lost first. Then, the dehydrated oxalic acid decomposes into carbon dioxide(CO2), carbon monoxide(CO) and water(H2O).
Equations involved :
H2C2O4 . 2H2O → H2C2O4 + 2H2O
H2C2O4 → CO2 + HCOOH (FORMIC ACID)
HCOOH → CO + H2O
Overall equation : H2C2O4.2H20 → CO2 + CO + H2O
Answer: There are few simple rules to follow.
(1) The atomic number is equal to the number of protons.
Z
= number of protons
(2) In neutrally charged elements, the number of electrons is the same as the number of protons.
Z
= number of protons = number of electrons (no charge)
Otherwise, positive charge means that the element lost an electron and negative charge means it gained an electron.
(3) The atomic mass is equal to the sum of the number of protons and number of neutrons.
A
= number of protons + number neutrons
or
A
=
Z
+ number neutrons
So if you say that
Z
= 20 and
A
= 40, then
A
=
Z
+ number neutrons
40 = 20 + number of neutrons
40 - 20 = number of neutrons
Therefore,
number of neutrons = 20
Explanation:
Answer:
compounds , because they're combined
