The percentage of hydrogen in C7H18 is calculated as follows:
[18/(12*7+1*8)]*100=18%
The amount of hydrogen in 5.2moles is given by:(18/100)*5.2=0.94moles
Answer:
4.68x10²⁵ ions of Na⁺
Explanation:
First of all, we dissociate the salt:
NaCl(aq) → Na⁺(aq) + Cl⁻(aq)
An aqueous solution of NaCl dissociates in chlorides anions and sodium cations. Ratio is 1:1, per 1 mol of NaCl, we have 1 mol of Na⁺
We determine the moles of salt: 4543.3 g . 1mol / 58.45 g = 77.7 moles
77.7 moles are the amount of NaCl, therefore we have 77.7 moles of Na⁺.
We count the ions:
1 mol fo Na⁺ has 6.02x10²³ ions
77.7 moles of Na⁺ must have (77.7 . 6.02x10²³) / 1 = 4.68x10²⁵ ions of Na⁺
Answer:
The specific heat of sodium is 1,23J/g°C
Explanation:
Using the atomic weight of sodium (23g/mol) and the atomic weight definition, we have that each mole of the substance has 23 grams of sodium.
starting from this, we use the atomic weight of sodium to convert the units from J / mol ° C to J / g ° C

Throughout the metallic structure allowing the atoms to slide past each other. This sliding is why metals are ductile and malleable. Ioniccompound must break bonds to slide past one another, which causes the ionic material to split and crack.