Answer:
1.79 mol.
Explanation:
- For the balanced reaction:
<em>2NaCl + F₂ → 2NaF + Cl₂.
</em>
It is clear that 2 mol of NaCl react with 1 mol of F₂ to produce 2 mol of NaF and 1 mol of Cl₂.
- Firstly, we can get the no. of moles of F₂ gas using the general law of ideal gas: <em>PV = nRT.</em>
where, P is the pressure of the gas in atm (P = 1.2 atm).
V is the volume of the gas in L (V = 18.3 L).
n is the no. of moles of the gas in mol (n = ??? mol).
R is the general gas constant (R = 0.0821 L.atm/mol.K),
T is the temperature of the gas in K (299 K).
∴ no. of moles of F₂ (n) = PV/RT = (1.2 atm)(18.3 L)/(0.0821 L.atm/mol.K)(299 K) = 0.895 mol.
- Now, we can find the no. of moles of NaCl is needed to react with 0.895 mol of F₂:
<em><u>Using cross multiplication:</u></em>
2 mol of NaCl is needed to react with → 1 mol of F₂, from stichiometry.
??? mol of NaCl is needed to react with → 0.895 mol of F₂.
∴ The no. of moles of NaCl needed = (2 mol)(0.895 mol)/(1 mol) = 1.79 mol.
Answer:
Volume = 3.86 ml (Approx)
Explanation:
Given:
Density of cadmium = 8.65 g/ml
Mass of pure object = 33.4 g
Find:
Volume pure cadmium
Computation:
Volume = Mass / Density
Volume = 33.4 / 8.65
Volume = 3.86 ml (Approx)
The 3 and 2 to the right of the components are subscriptions.
Answer: half life
Explanation: Radioactive decay follows first order kinetics and the time required for the decay of a radioactive material is calculated as follows:
t= time required
k= disintegration constant
x= amount of substance left after time t
a= initial amount of substance
when one half of the sample is decayed, one half of the sample remains and t can be represented as 
at 
, 
Halogens are a group of elements consisting of Fluorine, Chlorine, Bromine, Iodine and Astatine. In their ionic form, they have a superscript of -1, for example, chloride ion is Cl-1. These means that they readily accept one electron in order to achieve the Octet rule. The Octet rule states that each atom must contain 8 electrons in their valence shell for it to be stable. The most stable set of elements are the noble gases. Because they already fulfill the Octet rule, they no longer take part in reactions. Halogens are also very electronegative, meaning, they attract more electrons toward them. This is also a consequence of the Octet rule.
From the choices, the answers would be:
<span>they require only one electron to complete their outer shell
they have a high electronegativity</span>
