Answer:
2NaCN + CaCO3 --> Na2CO3 + Ca(CN)2
Explanation:
Knowing the names gets us: NaCN + CaCO3 --> Na2CO3 + Ca(CN)2
Balance: there are two sodiums and cyanides on the product side so add a 2 to the reactant side.
A halide ion is a halogen atom bearing a negative charge. The halide anions are fluoride (F−), chloride (Cl−), bromide (Br−), iodide (I−) and astatide (At−). Such ions are present in all ionic halide salts. Halide minerals contain halides.
<span>The answer to this question would be: placement of electrons only
An atom with resonance structure or mesomerism has one or more different structure with different placement of the electron. The atom should have a same amount of electron but only differ in the electron position. This will result in a different Lewis structure model. In this structure, you can find </span>π electrons pair.<span>
</span>
Explanation:
The given data is as follows.
Pressure (P) = 170 torr, mass of heptane (m) = 86.7 g
First, we will calculate the number of moles as follows.
No. of moles = 
= 
= 0.867 mol
Now, the number of moles of
are calculated as follows.
No. of moles = 
=
= 1.07
Therefore, mole fraction of heptane will be calculated as follows.
Mole fraction =
= 
= 
= 0.445
Now, we will calculate the partial pressure of heptane as follows.

=
= 75.65 torr
Thus, we can conclude that the partial pressure of heptane vapor above this solution is 75.65 torr.
Answer:
Stars are made of very hot gas. This gas is mostly hydrogen and helium, which are the two lightest elements. Stars shine by burning hydrogen into helium in their cores, and later in their lives create heavier elements.Stars are huge celestial bodies made mostly of hydrogen and helium that produce light and heat from the churning nuclear forges inside their cores.