Hydrogen fluoride gas (HF) and sodium hydroxide (NaOH) react in a test tube. They form water and sodium fluoride (NaF). Which type of reaction occurred in the test tube?
single–replacement reaction
decomposition reaction
acid–base reaction
synthesis reaction

Question

Hydrogen fluoride gas (HF) and sodium hydroxide (NaOH) react in a test tube. They form water and sodium fluoride (NaF). Which type of reaction occurred in the test tube?
single–replacement reaction
decomposition reaction
acid–base reaction
synthesis reaction

anonymous · Answer

HF is an acid (albeit a weak one) and NaOH is a base. Given this information, which do you think is the best answer?

anonymous · Answer

Also, always keep in mind that 
$$\text{Acid}+\text{Base}\rightarrow \text{Water}+\text{Salt}$$This is a huge indicator of acid-base reactions.