The answer is same atomic number!
Impossible to form from given reactants
Explanation:
Only sodium has carbonate ion here .so only possible way to displace carbonate is to use potassium
When sodium carbonate and Potassium iodide react with each other double displacement reaction occurs
As potassium is powerful than sodium it displaces sodium to form potassium carbonate .
Then you have to use water and then you can use calcium suppliment .
Helium (He) has the lowest melting point of <span>-272.2 °C.</span>
Answer:
- 178 ºC
Explanation:
The ideal gas law states that :
PV = nRT,
where P is the pressure, V is the volume, n is number of moles , R is the gas constant and T is the absolute temperature.
For the initial conditions :
P₁ V₁ = n₁ R T₁ (1)
and for the final conditions:
P₂V₂= n₂ R T₂ where n₂ = n₁/2 then P₂ V₂ = n₁/2 T₂ (2)
Assuming V₂ = V₁ and dividing (2) by Eqn (1) :
P₂ V₂ = n₁/2 R T₂ / ( n₁ R T₁) then P₂ / P₁ = 1/2 T₂ / T₁
4.10 atm / 25.7 atm = 1/2 T₂ / 298 K ⇒ T₂ = 0.16 x 298 x 2 = 95.1 K
T₂ = 95 - 273 = - 178 º C
Answer:
Explanation:
Our 
sample yielded 1g of 
and 16g of 
, but our unknown sample yielded 2 times as much for the same amount of .
What does this mean? that the H:O proportion for the unknown sample is twice the H:O proportion for the sample.
What is the H:O proportion for the sample? As we can see from its formula, it's 1:1, therefore the proportion for the unknown formula must be 2:1.
That means, two H atoms for every O atom. We could write that as: 
and you should recognize that formula, for it is one of the most common compounds on earth, Water.
