Answer : (a) is a decomposition reaction.
Explanation :
(a) is a decomposition reaction.
(b) is a displacement reaction.
(c) is a combination reaction.
(d) is a combustion reaction.
Therefore, option (a) is a decomposition reaction.
3 billion
4 ½ billion
6 ½ billion
Answer is 4 ½ billion.
Scientists think the earth's age is 4 ½ billion. This calculation is based on the radioactive dating. Since the formation of the earth, the time period has been divided into 3 major geological time periods as eon. They are phanerozoic, proterozoic and archean.
Scientists estimate that the Earth is approximately 4.5 billion years old based on radiometric dating and other lines of evidence.
The correct answer is 4 ½ billion years. Scientists believe that the Earth is approximately 4.5 billion years old based on evidence from radiometric dating of rocks on Earth and meteorites. Radioactive elements such as uranium and potassium decay into stable isotopes over time, and by measuring the ratio of parent isotopes to daughter isotopes in rocks, scientists can estimate the age of the Earth.
This estimation is supported by other lines of evidence, such as the age of the oldest rocks on Earth and the Moon, and the ages of meteorites. These findings suggest that the Earth formed shortly after the formation of the Solar System, which is estimated to be about 4.6 billion years old.
Therefore, the most accurate estimation is that the Earth is approximately 4.5 billion years old.
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Answer: The ratio of the number of oxygen molecules to the number of nitrogen molecules in these flasks is 1: 1
Explanation:
According to avogadro's law, equal volumes of all gases at same temperature and pressure have equal number of moles.
According to avogadro's law, 1 mole of every substance contains avogadro's number of particles.
Thus as oxygen and nitrogen are at same temperature and pressure and are in equal volume flasks , they have same number of moles and thus have same number of molecules.
The ratio of the number of oxygen molecules to the number of nitrogen molecules in these flasks is 1: 1
The ratio of the number of oxygen molecules to the number of nitrogen molecules in the two flasks is 8/7.
The ratio of the number of oxygen molecules to the number of nitrogen molecules in the two flasks can be determined using Avogadro's law, which states that equal volumes of gases at the same temperature and pressure contain equal numbers of molecules. Since both flasks have the same volume, temperature, and pressure, the ratio of oxygen molecules to nitrogen molecules will be equal to the ratio of their molecular masses.
The molecular mass of oxygen is 32, while the molecular mass of nitrogen is 28. Therefore, the ratio of the number of oxygen molecules to the number of nitrogen molecules will be:
32/28, or 8/7.
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B. cooled rapidly.
C. subjected to a small voltage.
D. exposed to weak light.
Answer:
A. bombarded by high-speed electrons.
Explanation:
Conductors are materials that allows current to pass through them.
However, the flow of current is actually the flow of electrons in the opposite direction.
When a conductor is bombarded by by high-speed electrons, the high speed electrons will repel the electrons in the conductor (in electromagnetism, like charges repel) thus giving them the required kinetic energy to leave the surface of the conductor.
(2) The block gains heat from the water until both are at 90.0°C.
(3) The water loses heat and the block gains heat until both are at the same temperature that is between 10.0°C and 90.0°C.
(4) The water gains heat and the block loses heat until both are at the same temperature that is between 10.0°C and 90.0°C.
Heat transfers from the water to the copper block until both reach an equilibrium temperature.
The transfer of heat in this system can be described by (4) The water gains heat and the block loses heat until both are at the same temperature that is between 10.0°C and 90.0°C.
This is because heat always flows from the object with higher temperature to the object with lower temperature. In this case, the water at 90.0°C has a higher temperature than the copper block at 10.0°C. As a result, heat will transfer from the water to the copper block, causing the water to cool down and the copper block to heat up. Eventually, both objects will reach an equilibrium temperature somewhere between 10.0°C and 90.0°C.
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Answer:
calcium
Explanation: