The chalk particles embed themselves into the small pores on the surface.
Although a chalkboard seems smooth to the touch, it is quite rough at the microscopic level, with <em>pores</em> that reach below the surface.
When you drag chalk across the board, friction causes small particles of chalk to rub off onto the surface.
If you leave the markings for a long time, some of the chalk particles will work their way into the pores.
A brush will remove the surface particles, but <em>it will not be able to get at the particles in the pores</em>.
Control group: 50 dogs continuing their normal diet
Experiments group: 50 dogs chosen to eat the new food
Independent variable: dog food
Dependent variable: the dogs’ weight
1.50 mol C3H8 X (3 mol CO2 / 1 mol C3H8) X (44.0 g CO2 / 1 mol CO2) = 198 g CO2
One of the many awe-inspiring things about algae, Professor Greene explains, is that they can grow between ten and 100 times faster than land plants. In view of this speedy growth rate – combined with the fact they can thrive virtually anywhere in the right conditions – growing marine microalgae could provide a variety of solutions to some of the world’s most pressing problems.
Take, global warming. Algae sequesters CO2, as we have learned, but owing to the fact they grow faster than land plants, can cover wider areas and can be utilised in bioreactors, they can actually absorb CO2 more effectively than land plants. AI company Hypergiant Industries, for instance, say their algae bioreactor was 400 times more efficient at taking in CO2 than trees.
And it’s not just their nutritional credentials which could solve humanity’s looming food crisis, but how they are produced. Marine microalgae grow in seawater, which means they do not rely on arable land or freshwater, both of which are in limited supply. Professor Greene believes the use of these organisms could therefore release almost three million km2 of cropland for reforestation, and also conserve one fifth of global freshwater
Answer:
Strontium is a soluble earth metal with the nuclear number 38. Phosphate is a polyatomic particle containing phosphorus and oxygen molecules. Strontium loses electrons to turn out to be emphatically charged, and phosphate is an adversely charged particle.
Explanation:
