Answer:
moles H₂O = 10
Explanation:
The mass of Na₂CO₃⋅xH₂O is 3.837 g and the mass of Na₂CO₃ is 1.42g
Therefore the mass of xH₂O is 3.837 - 1.42 = 2.417 g
The molar mass of Na₂CO₃ is 106 g/mol and for H₂O is 18 g/mol
The moles of Na₂CO₃ and H₂O in the sample are:
Na₂CO₃ = 1.42 / 106 = 0.01340 moles
H₂O = 2.417 / 18 = 0.1343
Now using rule of three :
1 mole of Na₂CO₃ has x moles of H₂O
0.01340 moles of Na₂CO₃ has 0.1343 moles of H₂O
x = 1 * 0.1343 / 0.01340 = 10
A way to explain it is that back then all the continents were together but soon after drifted apart the were in the same place sort of put they drifted apart so that's sorta what happened. Hope that helps a little
Hiii
3. describe the physical characters that can be observed: phenotype
6. a specific characteristic of an organism: trait
7. a section of DNA that provides instructions for specific traits: genes
8. allele expressed in the phenotype even if only one copy is present in the genotype: dominant
hope this helped :)
Answer: a: reactants Na-2 Cl-2
Products: Na-2 Cl-2;
b: reactants P-1 Cl-13 H-6 Products P-1 H-6 Cl-13
c: reactants P-4 H-12 O-16
Products H-12 P-4 O-16
Explanation: since these equations are balanced the atoms on of element on the reactants side will be same as the atoms of the same element of the product side
Answer: The values for Ka and Kb for the species in solution must be known before a prediction can be made
Explanation:
1. If Ka is greater than Kb, the salt solution is acidic
2. If Ka is lesser than Kb, the salt solution is basic
3. If Ka is equal to Kb, the salt solution is acidic