A chemical change affects on the molecular level of matter, which makes it irreversible. Combustion is a pretty good exmple. Physical changes are reversible and dont alter the formula. Hope this helped!
Answer:
The correct answer is - 2770000 cm.
Explanation:
1 kilometer = 1000 meter
1 meter = 100 centimeter
1 kilometer = 100*1000 cm
1 km = 100000 cm.
then,
27.7 kilometers = 2.77 × 10^6 centimeters
So, 27.7 kilometers = 27.7 × 100000
= 2.77 × 106 or 2770000 centimeters.
Answer:
The mixture of ethanol and water is a liquid-liquid solution. The solvent is Water.
Explanation:
Answer: Precision means that measurements are close to each other . Accuracy means that measurements are close to accepted value
Explanation:
Precision refers to the closeness of two or more measurements to each other.
For Example: If we weigh a given substance five times and you get 5.0 kg each time. Then the measurement is very precise.
Accuracy refers to the closeness of a measured value to a standard or known value.
For Example: If the mass of a substance is 5.0 kg and one person weighed 4.9 kg and another person weighed 3.9 kg. Then, the weight measured by first person is more accurate.
Thus Precision means that measurements are close to each other . Accuracy means that measurements are close to accepted value.