From a solubility curve the solubility of KNO3 at 40°C is about 63 g / 100 g of water.
That means that 100 g of water at 40°C can dissolve 63 g of KNO3.
A saturated solution is one that cannot dissolve more solute, because it already has reached the greatest concentration that it can hold.
Then, the mass of KNO3 that dissolves in 100 g of water is about 63 g.
Answer:
The atomic number of<span>N<span>157</span></span>
The number of protons is 7
The number of electrons is 7
The number of neutrons is 8
Explanation:
The atomic number of Nitrogen is 7 because Nitrogen has 7 protons.
The seven protons attract 7 electrons in the ground state.
If the atom had fewer or more than 7 protons the atom would not be Nitrogen.
The mass of the atom is the sum of protons and neutron. so
p + n = mass ( protons (p) and neutrons(n) both have an atomic mass of one
7 + n = 15 subtract 7 from both sides
<span>7−7+n=15−7</span>
n = 8
As we know that Molarity is given as,
M = moles / V
Solving for V,
V = moles / M ------------------(1)
Also, moles is equal to,
moles = mass / M. mass -------------(2)
puting value of moles from eq. 2 into eq. 1,
V = (mass / M.mass) / M
Putting values,
V = (45 g / 164 g/mol) / 1.3 mol/dm³
V = 0.21 dm³
Answer:Hafnium is a chemical element with atomic number 72 which means there are 72 protons and 72 electrons in the atomic structure. The chemical symbol for Hafnium is Hf. Neutron Number and Mass Number of Hafnium Mass numbers of typical isotopes of Hafnium are 176-178, 179, 180.
Explanation:
In the north Atlantic the movement of tectonic plates(if that is what you meant by plates) is around.4 inches per year which is almost 1 cm but in the pacific area the movement is almost 2 inches which is more that four cm every year although some people say that they (in general not specific to any place in particular) travel in the range of 5-10 centimeters every year.