How many joules of heat are needed to raise the temperature of 40.0 g of aluminum from 67°C to 89°C, if the specific heat of aluminum is 0.89 J/g°C?

Grade 9 chemistry:

 Bob takes a break from singing and fills a balloon indoors where the temperature is 21 degrees Celsius (normal room temperature). Then, he puts the balloon in the fridge, where the temperature is 2 degrees Celsius. What will happen to his balloon? Why does this happen? 

Which situation will lead to the presence of dew most quickly?

◯ A. A rising humidity and a falling temperature.

◯ B. A falling humidity and a falling temperature.

◯ C. A falling humidity and a rising temperature.

◯ D. A rising humidity and a rising temperature.

Why aluminium don't catch the rust ?