<span>An exothermic reaction is one in which heat is released from the reagents into the ambient environment. Perhaps somewhat counterintuitively, condensation is in fact an example of such a reaction. During the process of the gas-to-liquid phase change, water goes from a higher-energy to lower-energy state of matter, and, as such, releases heat into the environment.</span>
First, we must know what happens in the precipitation reaction. This type of reaction is a double replacement reactions. It is consists of two reactant compounds which interchange cations and anions to form two products. One of the products is an insoluble solid called a precipitate. For the precipitation of CaCO₃, there are two consecutive reactions involved:
1. Slaking of quicklime, CaO
CaO + H₂O ⇒ Ca(OH)₂
2. Precipitation
Ca(OH)₂ + CO₂ ⇒ CaCO₃ + H₂O
The ions that make up the H₂O molecule are H⁺ and OH⁻. According to solubility rules, the cation (positively charged ion) is likely to be attracted to an anion (negatively charged ion). Together, they form an ionic bond. This type of bond is when there is a complete transfer of electrons between the two. The Ca²⁺ cation lacks 2 electrons, while the anion OH⁻ has an excess 1 electron. In order to be stable, 1 Ca²⁺ ion and 2 OH⁻ ions must combine.
Therefore, the answer is OH⁻ ion.
2.34 moles titanium x (6.022 x 10^23)/1 mole titanium = 1.41 x 10^24
The difference between an organ and a tissue is that basically tissues are a group of similar cells that works together. Then a group of tissue that works together would make up an organ. Groups of organ working together later makes up an organ system. This is the main difference between an organ and a tissue.
Explanation:
To answer this question, we'll need to use the Ideal Gas Law:
p
V
=
n
R
T
,
where
p
is pressure,
V
is volume,
n
is the number of moles
R
is the gas constant, and
T
is temperature in Kelvin.
The question already gives us the values for
p
and
T
, because helium is at STP. This means that temperature is
273.15 K
and pressure is
1 atm
.
We also already know the gas constant. In our case, we'll use the value of
0.08206 L atm/K mol
since these units fit the units of our given values the best.
We can find the value for
n
by dividing the mass of helium gas by its molar mass:
n
=
number of moles
=
mass of sample
molar mass
=
6.00 g
4.00 g/mol
=
1.50 mol
Now, we can just plug all of these values in and solve for
V
:
p
V
=
n
R
T
V
=
n
R
T
p
=
1.50 mol
×
0.08206 L atm/K mol
×
273.15 K
1 atm
= 33.6 L
this is not the answer but it will help you
do by the formula it is on the answer
