Answer:
C. plagioclase
Explanation:
From the magma silicate crystals are formed successively when the magma temperature reaches the typical melting temperature for each type of crystal. The first crystals formed at high temperatures can then change their composition or dissolve again. In this way the crystals already formed contribute their ions, molecules and atoms to magma and combine again forming new crystals whose melting temperature is lower than that of the first crystals formed. The new crystals are said to be stable at the lowest temperatures set now. These processes of change are called reactions. As several successive reactions occur as the magma temperature decreases the ordered series of reactions is called the BOWEN series in honor of the Canadian scientist who formulated this concept. There are two types of reactions, the continuous reaction and the discontinuous reaction.
<u>
By continuous reaction a crystal formed at high temperatures such as a plagioclase rich in the Ca2 +</u> component gradually varies its composition by replacing a portion of the Ca2 + ions with the Na + ions and a portion of the Al3 + ions with the Si4 + ions. To maintain its neutrality, the replacement of Ca2 + by Na + is coupled with the replacement of Al3 + by Si4 +. The series of continuous reaction starts from the plagioclase rich in Ca2 +, passes through several plagioclase of intermediate composition towards the plagioclase rich in Na +
Answer:
<u>Washington D.C</u> is the capital of America
Answer:
masagana
Explanation:
masagana tayo sa anyo tubing na dapat alagaan anyung lupa na ating napakinabangan ngunit .
South Africa is a country located at the southern tip of Africa. It has had a rich colonial history since the seventeenth century. In 1652, the Dutch came and founded a colony on the Cape.
After a century and a half of Dutch colonization, the Cape Colony was taken over by the United Kingdom. As a result, a large number of Dutch-speaking settlers, known as Boers, migrated inland with the Great Trek and founded several Boer states, of which the South African Republic and the Orange Free State were ultimately the most important. These republics were conquered by the British in 1902 in the Second Boer War and united together with the Cape Colony and Natal to form South Africa in 1910.
In the 20th century, South Africa was overshadowed by apartheid, a system of racial segregation that systematically disadvantaged the non-white population. Apartheid was abolished in 1990 and Nelson Mandela was elected South Africa's first black president in 1994.
South Africa is a country with diverse population groups and eleven official languages. The country is a parliamentary republic with three capitals and is one of the most developed countries in the continent, but poverty and crime rates remain high.
Learn more about Africa in brainly.com/question/14304779
