Answer:
Electrons have negative charge.
Answer:

Explanation:
Half time is period required to desintegrating the half of the initial number of atoms. Then, the total time is:


The data on Climate change is as explained below-
Explanation:
Climate change is the ominous “hard truth” concurrently. However, it is not the first time that climate change is happening. In geological history, we find plenty of evidence of climate change.
The most important and famous of all such changes is the climate change that occurred during the Mesozoic era leading to the extinction of Dinosaurus. The reason behind these all climate changes was different. However, the climate change we are witnessing at present has something extra to all this natural stuff.
The present climate change is fuelled by anthropogenic activities at large. Large scale emission of greenhouse gases possibly from burning of fossil fuels ever since the Industrial revolutions in the late 18th century has altered the chemical composition of atmospheric gases. In addition to the use of fossil fuels other activities such as agriculture, coal-based power plants, deforestation and other such activities have been instrumental in degrading the serene balance between different atmospheric gases.
The evidence of the present climate change can be gauged in-
- The rise in global average temperature-Earth’s mean temperature has risen by around 1° C ever since the 19th century. 2017 proved to be the warmest year in the record.
- Oceans have been net absorber of the heat. This has led to the warming up of oceans. This severely hampers and impact marine flora and fauna
- Deglaciation- the increasing temperature has manifested in the form of shrinking ice-sheets. Large icebergs are calving and thus has some serious long-term impact for the sustenance of mankind.
- Rise in the mean sea level- The sea level has risen by almost 10 inches since last century. This increase is all set to increase in future thus endangering the lives and livelihood of the coastal communities.
All the leading personalities of the time including the ex-president of the US Mr Barak Obama emphasised the importance of climate change and urged the global community to tackle it at earliest. In his words, he mentioned, “No other challenge poses as great a threat to the future generation as the climate change”. In addition to Mr Obama, noted climate activist Greta Thunberg described the climate change to be the greatest crisis to the humanity that it has ever faced.
Therefore, it can be safely argued that it’s urgent to talk and act tough on climate change. Climate change has transitioned into a multi-headed monster capable enough to devastate the entire mankind. It has done this earlier and sure to carry it further on.
<u>Answer:</u> The atom with 6 protons and 6 neutrons and an atom with 6 protons and 7 neutrons are the isotopes of same element.
<u>Explanation:</u>
Isotopes are defined as the chemical species that belong to the same element but differ in their mass number.
This also means that the chemical species have same number of protons and electrons but different number of neutrons.
Atomic number is defined as the number of protons or electrons that are present in a neutral atom.
Atomic number = number of protons = number of electrons
Mass number is defined as the sum of number of protons and neutrons that are present in an atom.
Mass number = Number of protons + Number of neutrons
From the given options:
The elements having same number of protons will be the isotopes of same element.
Hence, the atom with 6 protons and 6 neutrons and an atom with 6 protons and 7 neutrons are the isotopes of same element.