Photosynthesis is an endothermic chemical reaction that forms sugars from carbon dioxide, water, and the sun's energy. Which of the following must be true of photosynthesis?
The reaction can take place only if energy is added.
The reactants are oxidized.
The photosynthesis reaction produces ions.
The molecular bonds in carbon dioxide are very weak.
A student analyzes soil samples from her backyard. She organizes the samples into three categories, based on their pH. The three categories are: pH less than 8, pH between 8 and 8.5, pH greater than 8.5. Which type of graph should she use to show the percent of samples in each group?
stem and leaf plot
circle graph
line graph
scatter plot
Americium–241 decays into neptunium–237. Which correctly describes this process of radioactive decay?
An unstable nucleus decays into a more stable nucleus.
Energy in the nucleus is converted into mass.
The strong nuclear force splits the nucleus apart.
The atom loses four protons.
Why can beta particles pass through materials more easily than alpha particles?
Beta particles are made of pure energy.
Beta particles are smaller.
Beta particles are not charged.
Beta particles move more slowly.
I know it's a lot, but I really need help. Please.
The reaction can take place only if energy is added.
The reactants are oxidized.
The photosynthesis reaction produces ions.
The molecular bonds in carbon dioxide are very weak.
A student analyzes soil samples from her backyard. She organizes the samples into three categories, based on their pH. The three categories are: pH less than 8, pH between 8 and 8.5, pH greater than 8.5. Which type of graph should she use to show the percent of samples in each group?
stem and leaf plot
circle graph
line graph
scatter plot
Americium–241 decays into neptunium–237. Which correctly describes this process of radioactive decay?
An unstable nucleus decays into a more stable nucleus.
Energy in the nucleus is converted into mass.
The strong nuclear force splits the nucleus apart.
The atom loses four protons.
Why can beta particles pass through materials more easily than alpha particles?
Beta particles are made of pure energy.
Beta particles are smaller.
Beta particles are not charged.
Beta particles move more slowly.
I know it's a lot, but I really need help. Please.