yup pretty much.
Lemonade is anything fizzy with sugar in it. It's not usually used to describe the stuff that Charlie Brown and Lucy make and sell for 5 cents a cup - that's Lemon juice. So it's a generic term, but Lemonade also refers specifically to the product called Lemonade - that is, soda or pop that is just sugar and water without the food colouring and flavours. So Lemonade is lemonade, but so is Coke, Lime, 7-up, etc. Soda is only used of soda water - carbonated water with no sugar in it.