You are right, it's CA Calcium, 40.08, Group 2 and Row 4.
Answer: Different plant structure can increase chances of reproduction by the animals and other living organisms in the ecosystem.
Explanation: Plants like flowers can be pollinated by bees . The bees carry the pollen and this can increase chances of reproduction. Plants like plums that have large seeds can increase chances of reproduction by there fruit falling and rotting so the seed can be forced into soil. Different structures of plants can increase chances of reproduction through the animals, soil around the plant, as well as weather .
Whenever the fuel is being used up, a star explodes and the energy leakage from a star's core ceases.
Explanation:
The dying star expands in the "Red Giant," before even the inevitable collapse starts, due to nuclear reactions just outside of the core.
It becomes a white dwarf star when the star has almost the same density as the Sun. If it's much larger, a supernova explosion could take place and leave a neutron star away. However, if it is very large–at least three times the Sun's mass–the crumbling core of the star, nothing will ever stop it from crumbling. The star is imploding into a black hole, an endless gravitational loop in space.
Answer:
Percent error = 25%
Explanation:
Given data:
Measured density of water = 1.25 g/mL
Accepted density value of water = 1 g/mL
Percent error = ?
Solution:
Formula:
Percent error = (measured value - accepted value / accepted value) × 100
Now we will put the values in formula:
Percent error = (1.25 g/mL - 1 g/mL /1 g/mL )× 100
Percent error = (0.25 g/mL /1 g/mL )× 100
Percent error = 0.25 × 100
Percent error = 25%
You should read up on Proust's law, better known as the Law of Definite Proportions. This is a chemical law that defines your question more generally, on why the ratio of elements and ions are always fixed.
Basically, this compound Magnesium(II) Chloride is MgCl2 because it has the same number of protons, neutrons, and electrons all the way. This defines the properties of the compound or atom.
