Answer:

Explanation:
The unbalanced nuclear equation is

We can insert the subscripts, because these are the atomic numbers of the elements

That leaves only the superscript of He to be determined,
The main point to remember in balancing nuclear equations is that the sums of the superscripts must be the same on each side of the equation.
Then
27 + x = 31, so x = 31 - 27 = 4
Then, your nuclear equation becomes

Explanation:
Van der Waals interactions occur between any two or more molecules. They are caused by a fluctuation in electron density, as electrons are not actually fixed in a shell, but actually freely moving as a 'cloud of electron density'. This means that sometimes one end of a molecule can become more partially negatively charged as all electrons move to that side, and conversely it can attract the more partially positive end of a molecule (that has little electrons).
Hydrogen bonds only occur between molecules that contain oxygen, nitrogen and fluorine bonded to a hydrogen atom.
Hydrogen bonding is also the strongest intermolecular force there is, but not strong in comparison to ionic and covalent bonds. Therefore, hydrogen bonds are much stronger than Van der Waals forces. Hydrogen bonds only form if oxygen, nitrogen and fluorine are bonded to a hydrogen atom, as they have the greatest electronegativity differences (look at an electronegativity table), and when the overall molecule is polar (have unequal charges). This allows the molecule to be able to attract another molecule from one of the bonded atoms to a hydrogen atom.
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:
Number of grams of mineral salt in one liter of water
.
Explanation:
Salinity :
It is the concentration of dissolved salts .
Salinity means the saltiness or the dissolved salt component in the water body . It is defined as mass (in gram) of the dissolved matter in the water bodies .
salts found in ocean water are :
Salts of chlorides, sulfates , sodium , magnesium, potassium and calcium
For example : world's oceans salinity is 3.5% parts per thousand (g/L) . It means 3.5 g of salt is present in 1 L of seawater .
Note : Sodium chloride is major salt found in ocean . But it is not the only salt present (other salts are also found) . So D can't be the answer
Answer:
most likely a microscope
Explanation:
Within optical microscopes, there are wide-field microscopes and confocal microscopes. Wide-field scopes include your basic light microscope, which has a lens or lenses to magnify visible light transmitted or reflected by a sample. They're good for looking at single layers of cells or thin tissues, Piston sai