Breakdown of Dollarinn er sterkari en krónan.
vera
to be
krónan
the króna (Icelandic currency)
sterkur
strong / spicy, hot (of food)
en
than
Questions & Answers about Dollarinn er sterkari en krónan.
Why is krónan in the nominative case here rather than taking an object case after en?
The word en (than) acts as a conjunction here, not a preposition, meaning it connects two parallel parts of a sentence. You can imagine an invisible verb at the end: The dollar is stronger than the króna (is). Since krónan is the subject of this implied second clause, it stays in the nominative case.
Since dollar is a foreign loanword, does it follow normal Icelandic declension rules?
Yes, Icelandic fully integrates loanwords into its grammar. Dollar is treated as a regular masculine noun. In this sentence, it takes the standard masculine nominative definite article suffix to become dollarinn. It also takes standard case endings in other contexts, like the genitive dollars.
Does the comparative adjective sterkari change its ending depending on the gender of the noun?
Yes, but comparative adjectives are much simpler than standard adjectives! They always decline weakly. For masculine and feminine nouns in the nominative case, the comparative ending is -ari (as seen here matching the masculine dollarinn). If you were describing a neuter noun, it would end in -ara.
Is it possible to express this comparison without using the word en?