Cevaplı Hemşirelik giriş sınavları için kimya çalışma kâğıdı

Between which kinds of elements do covalent bonds usually form?

1. ATwo nonmetals
2. BA metal and a noble gas
3. CA metal and a nonmetal
4. DTwo group 1 metals

What is an element?

1. AA physical mixture of different substances
2. BA substance made of only one kind of atom
3. CA substance of two or more elements chemically bonded together
4. DA particle with an electric charge

About what percentage of dry air is oxygen?

1. A78%
2. B21%
3. C50%
4. D1%

A student tests how temperature affects the rate of a reaction. What is the independent variable?

1. AThe reaction rate
2. BThe volume of acid, which is kept the same
3. CThe temperature
4. DThe type of beaker used

How many molecules are in 2 mol of carbon dioxide?

1. A1,20 × 10²⁴
2. B6,02 × 10²³
3. C3,01 × 10²³
4. D2,00 × 10²³

What is the mass of 0,5 mol of NaCl (molar mass 58,5 g/mol)?

1. A117 g
2. B29,25 g
3. C0,5 g
4. D58,5 g

Raising the temperature by 10 °C can roughly double the rate of many reactions. What is the main reason?

1. AThe activation energy itself is lowered by the extra heat
2. BMany more collisions have at least the activation energy
3. CThe reaction becomes more exothermic
4. DThe particles become larger and easier to hit

In the reaction NH₃ + H₂O ⇌ NH₄⁺ + OH⁻, which substance acts as the Brønsted–Lowry acid?

1. AH₂O
2. BNH₄⁺ only
3. COH⁻
4. DNH₃