Many compound nouns in English consist of an adjective and a noun. In constructions consisting of an adjective followed by a noun, it is the noun which carries primary stress. In a compound noun constructed of an adjective and a noun, however, it is the adjective which carries primary stress.
A house that is green is a green house with primary stress on "house". A place for growing plants and vegetables is a greenhouse with primary stress on "green". A house that is white is a white house with primary stress on "house" but the residence of the President of the United States is the White House with primary stress on "White". A suit that has gotten wet is a wet suit with primary stress on "suit" but the suit worn by a scuba diver is a wetsuit with primary stress on "wet".
Spelling is unimportant because compound nouns can be written as one word, two words or even hyphenated. For example, "softball" is a one-word compound, "high school" is a two-word compound and "two-thirds" is a hyphenated compound.
Sometimes compound nouns do not carry compound stress. In other words, certain compounds do not carry primary stress on the first syllable. Most English speakers use compound stress in "apple sauce" but not in "apple pie". Likewise, most use compound stress in "potato chips" but not in "potato soup". In the latter case, the familiarity of the item may be a factor. More people eat potato chips than potato soup. However, this does not explain "apple pie" which is a popular dessert but is not pronounced with compound stress by most speakers.
Also interesting is that compounds with "cake" carry compound stress but compounds with "pie" usually do not. For example, the compounds "carrot cake", "plum cake", "lemon cake" and "cheesecake" carry first-syllable stress but in the English of most speakers the compounds "cherry pie", "pecan pie", "peach pie" and "lemon pie" do not.
However, the compound "chocolate cake" is a compound noun which many speakers do not pronounce with compound stress. This may be due to the syllabic structure of the compound. Speakers who stress the word "cake" in the compound "chocolate cake" use strong stress followed by weak and strong stresses to give the compound a regular rhythm. However, those who stress the first syllable use compound stress but use strong stress followed by two weak stresses to produce a rhythm which is less regular. In any case, not all compound nouns in English use compound stress.
Many of the compound nouns in English consist of an adjective and a noun. The stress of these compounds is different from the stress of constructions with an adjective and a noun. Compound nouns formed from an adjective and a noun carry primary stress on the adjective but constructions with an adjective and a noun carry primary stress on the noun. However, many compound nouns are an exception to this rule.