Answer:
Around 450 B.C.
Explanation:
The idea was forgotten until the 1800 when John Dalton re-introduced the atom.
Answer:
In water hydrogen bonding formed between partially negative oxygen and partially positive hydrogen atoms.
Explanation:
Hydrogen bond is a partially electrostatic attraction between hydrogen (H), which is bonded to a more electronegative atom such as nitrogen (N), oxygen (O) or fluorine (F), and another adjacent atom bearing a lone pair of electrons.
In water molecule hydrogen and oxygen have difference in electronegativity, due to which dipoles are form. One is partial positive on hydrogen atom and other is partial negative on oxygen atom. The electrostatic attraction occur between two oppositely charged poles which is known as hydrogen bonding.
The heat from the hotter water will go into the colder water untl equilibrium is reached. Equilibrium is same temperature!
Now, the heat is proportional to the mass, the specific heat and the temperature difference. The specific heat does not matter since all is water, it will cancel out:
m_1 * c_H20 * ( T_final - T_1 ) = -m_2 * c_H20 * ( T_final - T_2)
Notice the minus, because one wins the heat of the one who loses it. In this way both sides have the same sign:
m_1*(T_final - T_1)=-m_2*(T_final-T_2), or after some simple algebra:
T_final = (m_1 * T_1 + m_2 * T_2 )/(m_1+m_2),
which looks like an arithmetic mean, and one could have gone for this, but the above shows all the work. Notice that if T_1=T_2, T_final=T_1 always, which makes sense.
Now you can convert volume to mass with the density, but since mass = density*volume and it is all water, the density will cancel out and you can work with volumes. If you prefer just say: 120 ml->120 g , etc ...
T_final = (120*95+320*25)/(320+120)=44.0909 degrees Celsius, or ~ 44.09 degrees with two decimal precision as your statement (beware of precision always!).
Answer:
true.nitric acid reacts with those chemicals to form aqueous nitric acid
Answer : The volume of water added are, 15 mL
Explanation :
Formula used :

where,
are the initial molarity and volume of HCl.
are the final molarity and volume of water.
We are given:

Putting values in above equation, we get:

Hence, the volume of water added are, 15 mL