Answer: -
²²³Ra is the daughter nuclide produced when ²²⁷Th undergoes alpha decay
Explanation: -
When alpha decay occurs, the mass number of the parent decreases by 4 and the atomic number decreases by 2.
Mass number of ²²⁷Th =227
Atomic number of ²²⁷Th = 90
Mass number of daughter = 227 - 4 = 223
Atomic number of daughter = 90 - 2 = 88
88 is the atomic number of Ra Radium.
Thus the daughter is ²²³Ra
Answer:
The correct answer is D. How gravity interacts with planets
Explanation:
Einstein's theory of relativity formulated in 1915 introduces the following concepts:
- Formula E = mc2 (relationship between energy, mass, speed of light)
- How nuclear energy is produced
-After seeing a solar eclipse, gravity is interpreted geometrically (which is an effect of distortion)
-Relative time
Answer:
The outer core of the earth is liquid.
Explanation:
Seismic waves travel through the Earth at different speeds and are reflected and refracted diffracted differently as they encounter layers of different densities.
By analyzing these waves, they have concluded that there is an inner core of solid iron surrounded by a liquid outer core consisting of nickel and iron.
A is wrong. The Earth consists of several layers
C is wrong. Seafloor spreading is caused by the movement of tectonic plates away from each other.
D is wrong. The mantle is mostly solid rock.
Put the mixture in water, the pebbles will sink, the pepper will float, and the sugar will dissolve
