Scheda di esercizi di Chimica per i test di ammissione a infermieristica con soluzioni

Which element is a metalloid?

1. ASilicon
2. BArgon
3. CSulfur
4. DSodium

Quale tipo di legame tiene insieme il cloruro di sodio (sale da cucina)?

1. AIl legame ionico
2. BIl legame covalente
3. CIl legame metallico
4. DIl legame a idrogeno

Which electrons take part in chemical bonding?

1. AThe electrons closest to the nucleus
2. BThe valence (outermost) electrons
3. COnly the electrons in the first shell
4. DAll electrons take part equally

When a nucleus emits a beta particle, how do its mass number and atomic number change?

1. AMass number falls by 4 and atomic number falls by 2
2. BMass number rises by 1 and atomic number stays the same
3. CBoth fall by 1
4. DMass number stays the same and atomic number rises by 1

Water climbs up a narrow glass tube. Which property mainly causes this?

1. AWater's high boiling point
2. BLow density of water
3. CEvaporation of water from the tube
4. DAdhesion of water to the glass

Which of these is a colloid?

1. ASalt water
2. BSand in water
3. CMilk
4. DPure water

Quale equazione è bilanciata correttamente?

1. ANa + Cl → NaCl₂
2. B2Na + Cl₂ → 2NaCl
3. CNa + Cl₂ → NaCl
4. D2Na + Cl₂ → NaCl₂

For N₂ + 3H₂ → 2NH₃, 1 mol of N₂ is mixed with 2 mol of H₂. Which reactant is limiting?

1. AN₂, because there is less of it
2. BNH₃, because it is the product
3. CH₂, because 1 mol of N₂ would need 3 mol of H₂
4. DNeither, because both are used up exactly