A student investigates the rate of reaction between magnesium and hydrochloric acid. The reaction gives off hydrogen gas. The student wants to investigate how changing the concentration of the hydrochloric acid affects the rate of reaction. Look at her plan. First experiment I will put 0.5 g of magnesium ribbon into the flask. I will add 50 cm3 of hydrochloric acid. I will measure how fast the gas is given off. Second experiment I will put another 0.5 g of magnesium ribbon into the flask. I will add 100 cm3 of the same hydrochloric acid. I will measure how fast the gas is given off. Another student thinks that the plan will not work and he does not understand exactly what he has to do. Suggest how the plan for this investigation can be improved.

h let me think

answer : a model is often used to explain and make things easier to understand when any scientific topic needs to be demonstrated and explained.

as in this case where a scientist wants to use a model to present the results of his detailed scientific investigation. he should do it as it will him to make the audience understand the concept in a much better way. also, it can be changed according to new scientific understandings.

i don't see a text, but i am gonna assume this *orbit* the curved path, usually elliptical, described by a planet, satellite, spaceship, etc., around a celestial body, as the sun.

they it depends on if one believes about radioactivity, they make a geiger counter beep but maybe it was going to beep anyway electronics do wierd things all the time or it was programmed to beep near certain metals.