Užduočių lapas tema Chemija slaugos stojamiesiems egzaminams su atsakymais

Koks yra natrio cheminis simbolis?

1. ANa
2. BS
3. CN
4. DSo

Which of these is a chemical property?

1. ABoiling point
2. BColour
3. CDensity
4. DFlammability

How does increasing the concentration of a reactant in solution usually affect the reaction rate?

1. AThe rate decreases
2. BThe rate increases
3. CThe reaction stops
4. DThe rate stays the same

Which of these is a colloid?

1. APure water
2. BSalt water
3. CSand in water
4. DMilk

According to the Brønsted–Lowry definition, what is an acid?

1. AA proton (H⁺) acceptor
2. BA proton (H⁺) donor
3. CAn electron pair donor
4. DA hydroxide ion donor

Why does ice float on liquid water?

1. AIce contains trapped air from the freezer
2. BIce is denser than liquid water
3. CIce has a higher mass than the same volume of water
4. DIce is less dense than liquid water

A student tests whether water temperature affects how fast sugar dissolves. Which set of factors should be kept the same in every trial?

1. AOnly the colour of the cup
2. BNothing, because changing several factors at once gives more useful data
3. CThe mass of sugar, the type of sugar, the volume of water and the amount of stirring
4. DThe water temperature and the dissolving time

Alkanes follow the general formula CₙH₂ₙ₊₂. What is the formula of the alkane with 4 carbon atoms?

1. AC₄H₁₂
2. BC₄H₈
3. CC₄H₁₀
4. DC₄H₆