sentences: carbon dioxide is a kind of gas & baking soda can react chemically with vinegar producing carbon dioxide ->  baking soda can react chemically with vinegar producing a gas  vinegar is a kind of substance & baking soda is a kind of substance ->  combining baking soda and vinegar is combining two substance together  baking soda can react chemically with vinegar producing a gas & combining baking soda and vinegar is combining two substance together ->  combining baking soda and vinegar can cause chemical reactions  combining baking soda and vinegar can cause chemical reactions & vinegar is added into baking soda -> vinegar being added into baking soda will cause chemical reactions