Answer:
Group 8 elements are inert and possess :
1. Low Boiling Points
2. High ionization energies
3. Electronegativities is very low
4. No color, odor
Explanation:
Group 8 elements are also called as Noble Gases. They are unreactive.
They have low boiling points means they remains monoatomic at room temperature. Having high ionization energy means that it is very difficult to remove an electron from its valence shell.
Answer: 1145.8 years
Explanation:
Half-life of carbon-14 = 5720 years
First we have to calculate the rate constant, we use the formula :


Now we have to calculate the age of the sample:
Expression for rate law for first order kinetics is given by:

where,
k = rate constant = 
t = age of sample = ?
a = let initial amount of the reactant = 100 g
x = amount decayed = 75 g
a - x = amount left after decay process = 100 - 75 = 25g
Now put all the given values in above equation, we get


+4 and +6 I think not sure tho
298 g of calcium carbonate CaCO₃
Explanation:
We have the following chemical reaction:
CaCN₂ (s) + 3 H₂O (l) → CaCO₃ (s)+ 2 NH₃ (g)
number of moles = mass / molar weight
number of moles of H₂O = 161 / 18 = 8.94 moles
Knowing the chemical reaction we devise the following reasoning:
if 3 moles of H₂O produces 1 mole of CaCO₃
then 8.94 moles of H₂O produces X moles of CaCO₃
X = (8.94 × 1) / 3 = 2.98 moles of CaCO₃
mass = number of moles × molar weight
mass of CaCO₃ = 2.98 × 100 = 298 g
Learn more about:
number of moles
brainly.com/question/1445383
brainly.com/question/516702
#learnwithBrainly
Covalent bonds are formed when electrons are shared between elements that are nonmetals. The ammonium ion, NH+4 , would have covalent bonds because both nitrogen and hydrogen are nonmetals. ... So, the bond between this particular hydrogen atom and the central nitrogen is a dative covalent bond.