Answer: 3. The half- life of the isotope must be long enough to capture the age of the rock. and
4. their should be more than one unstable isotope.
In radioactive dating proces, the parent isotope is in unstable state which undergoes decay process to give stable daughter isotopes. Half-life is the amount of time it takes for half of the parent isotopes to decay. The rock dating requires a long lived parent isotope so that it can capture the exact rock age.
One rock when get decayed in the daughter isotope other will be available identify the age.
Answer:
d. The normal pH of human blood is already in the alkaline range.
Explanation:
The blood has an average pH between 7.35 and 7.45. Also, in blood there are some natural buffers that allows to maintain this pH does not matter the kind of food or substances that enter to our body.
If for any process the pH decreases a little bit, the body starts a process to recover the natural pH of the blood.
<span>Water covers around 70% of the Earth's surface and its high specific heat plays a very important role as it is able to absorb a lot of heat without a significant rise in the temperature. When temperatures decrease, the heat which is stored is released, restraining a rapid drop in temperature. The combined effect of these processes is a buffering of temperature on the Earth.</span>
In this
case, when Alicia is being tickled by her older sister, the divisions of
the nervous system which are responsible for receiving the signals from her
sister’s fingers are called somatosensory cortex and anterior
cingulated cortex nervous system.
When you are touched lightly, the effect of having that ticklish
sensation is caused by the analysis of two regions of the brain. For example,
when our brain analyses the pressure of the touch, this is the work of
the somatosensory cortex. On the other hand, as
soon as something touches your skin, the signal sent from the skin's sensory
receptors also passes through the anterior cingulated cortex.<span>This is
where the pleasant feelings are governed. </span>
The ansseer is Iridium.
The atomic number of iridium is 77 and it comes just before platinum (atomic number = 78).
In iridium,
The number of electrons = no. Of protons = 77.
The no. Of electrons and the no. Of protons is same as atomic number.
