A satellite has been transmitting weather data daily for three years. Suddenly, the transmission has been interrupted, and further transmissions are not clear. Which of these
features of the sun might have caused this change?
A. the photosphere
B. the chromosphere
C. a sunspot
D. a solar flare

What is a metal replacement reaction

100 grams of molten lead (600°c) is used to make musket balls. if the lead shot is allowed to cool to room temperature (21°c), what is the change in entropy (in j/k) of the lead? (for the specific heat of molten and solid lead use 1.29 j/g⋅°c; the latent heat of fusion and the melting point of lead are 2.45 × 104 j/kg and 327°c, respectively.)

40dm3 of gas at 760 torr are heated from 5°c to 50°c what is the new volume