Ozone which is present in the stratospheric region of atmosphere is helpful for preventing harmful UV rays from reaching the surface of earth. Due to human activity, several compounds (specifically chlorofluorocarbons) are released in atmosphere. Due to inherent chemical stability of these compounds, the remain stable in lower region of atmosphere and slowly diffuse into stratosphere. On reaching the stratosphere, these compounds reacts with ozone and thereby depletes the effective concentration of ozone present in atmosphere. Hence, <span>the Montreal Protocol was signed in 1987 by major countries of the world. This aim of this protocol was to protect the stratospheric ozone layer by phasing out the production and consumption of ozone-depleting substances.</span>
Answer:
Verdadero (True).
Explanation:
Después de la desintegración del citado virreinato, los nuevos Estados intentaron establecer sus fronteras, a menudo a través de guerras e invasiones. Cabe destacar la invasión brasileña de Uruguay o la Guerra de la Triple Alianza. En menor medida, lo hicieron a través de tratados internacionales. (After the disolution of the viceroyalship described above, the new States attempted to establish their frontier usually by wars and invasions. It is to highlight the Brazilian invasion of Uruguay or the Triple Alliance' War. In a lesser extent, they made it through international treaties.)
Answer:
Pb^+7
Explanation:
I placed the carrot there to signify the +7 is supposed to be small. It is plus seven because seven nuetrons are added
Answer:
54 g
Explanation:
1 mole of water = H2O
mass of 1 mole of H2O= mass of h2 + mass of o
= 2× mass of h +mass of o
= 2×1+16 =18 g
1 mole of water = 18g
3moles of water = 18×3g= 54g