Answer:
Number of Na ions in 14.5 g of NaCl is 1.49 × 10²³.
Number of Cl ions in 14.5 g of NaCl is 1.49 × 10²³.
Total number of ions = 1.49 × 10²³ + 1.49 × 10²³ = 2.98 × 10²³.
Explanation:
1 mole of any compound contains 6.023 × 10²³ molecules.
molecular weight of NaCl is 23 + 35.5 = 58.5 g.
so, 58.5 grams of NaCl makes 1 mole
⇒ 14.5 g of NaCl = = 0.248 moles.
⇒ 0.248 mole contains 0.248 × 6.023×10²³ molecules
= 1.49 × 10²³ molecules.
And 1 molecule contains 1 Na ion and 1 Cl ion.
⇒ number of Na ions in 14.5 g of NaCl is 1.49 × 10²³.
⇒ number of Cl ions in 14.5 g of NaCl is 1.49 × 10²³.
Total number of ions = 1.49 × 10²³ + 1.49 × 10²³ = 2.98 × 10²³.
Answer: Measuring the age of fingerprints is important because it can help detectives on a crime.
With fingerprints you can find the criminals record. Which would lead to their eventual arrest and a solved case.
Explanation:
Answer: 36.51L
Explanation:Please see attachment for explanation
Answer:
6.02 x 10²⁰ molecules
Explanation:
Given parameters:
Volume of nitrogen = 120cm³
Unknown:
Mass of Nitrogen = ?
Number of molecules present in it = ?
Solution:
At STP;
1 mole of a substance contains 22.4dm³ particles
100cm³ = 1dm³
24cm³ will give 0.024dm³
22.4dm³ of particles are in 1 mole of substances at STP
0.024dm³ of particles will contain = 0.001mole
Mass of Nitrogen = Number of moles x molar mass
molar mass of nitrogen = 14g/mol
Mass of nitrogen = 0.001 x 14 = 0.014g
Number of molecules present;
1 mole of a substance contains 6.02 x 10²³ molecules
0.001 mole of Nitrogen will contain 0.001 x 6.02 x 10²³ = 6.02 x 10²⁰
6.02 x 10²⁰ molecules