Plutonium<span> is </span>made<span> from U-238. Pu-239 is normally </span>created<span> in nuclear reactors by transmutation of individual atoms of one of the isotopes of uranium present in the fuel rods. Occasionally, when an atom of U-238 is exposed to neutron radiation, its nucleus will capture a neutron, changing it to U-239.</span>
Answer:
2, the acid is H₂X.
Explanation:
- It is known at equivalence point: the no. of millimoles of base is equal to the no. of millimoles of acid.
<em>∴ (nMV) of NaOH = (nMV) for HnX.</em>
where, n is the no. of producible H⁺ or OH⁻ of the acid or base, respectively.
M is the molarity of the acid or base.
V is the volume of the acid or base.
n = 1, M = 0.4 M, V = 0.6 L.
n = ???, M = 0.3 M, V = 0.4 L.
∴ n for HnX = (nMV) of NaOH / (MV) for HnX = (1)(0.4 M)(0.6 L)/(0.3 M)(0.4 L) = 2.
∴ the acid is H₂X.
Answer:
The atmosphere refers to the gaseous envelope of earth, comprised of variable gases with definite proportions. The layers of the earth's atmosphere are as follows-
- Troposphere- This layer starts from the ground and extends up to a height of about 10 km. Here, the temperature decreases with the increasing altitude. All the weather phenomenon takes place in this layer.
- Stratosphere- It starts from 10 km and extends up to a height of about 50 km. Here the temperature increases as the altitude increase. This is because of the presence of the ozone layer that receives the harmful UV radiation emitted from the sun.
- Mesosphere- This layer extends from a height of about 50 km to about 80 km above the earth's surface. Here, again the temperature decreases with the increasing altitude.
- Thermosphere- This layer starts from a height of about 80 km and extends up to about 500 km above the ground surface. In this region again the temperature increases with the increasing elevation.
- Exosphere- This layer ranges from about 500 km to 10,000 km above the earth's surface. Here, the temperature gradually increases with the increasing height.
This variation in temperature occurs because of the certain reason. In the troposphere and the mesosphere, the temperature decreases with height because the pressure and height are inversely proportional to each other. The stratosphere experiences increasing temperature because of the presence of the ozone layer that is responsible for holding the greenhouse gases and the harmful UV radiation. The thermosphere and the exosphere experience high temperatures because of the receiving of the direct sunlight. Due to these above reason, there occurs this temperature change in a unique pattern.
Answer:
The correct option is;
D. All the elements in families 1 and 2 can place all their shell electrons in the s sub-level
Explanation:
The elements in families 1 and 2 also called the group 1A and group 2A elements are known as the alkali and alkaline earth metals. The elements in the families 1 and 2 are also referred to as the s-block elements as they have their valence electrons which are 1 and 2 respectively, in the s-orbital or s sub-level
Due to their low ionization energy, and the ease with which they donate their valence electrons, elements of the families 1 and 2 are known to be very reactive, and are found in a combined state in nature.
