Answer:
The statement that is not true is: 'Temperature does not affect the reaction rate'.
Explanation:
a) Temperature can change a reaction rate. <u> This is true</u>
Increasing the temperature increases the reaction rates because of the disproportionately large increase in the number of high energy collisions. It is only these collisions (possessing at least the activation energy for the reaction) which result in a reaction.
For example, the time taken to melt a metal will be much higher at a lower temperature but it will decrease as soon as we increase the temperature
b) The amount of reactants can increase the reaction rate.<u> This is true</u>
A higher concentration of reactants leads to more effective collisions per unit time, which leads to an increased reaction rate.
c) Temperature can decrease the reaction rate. <u>This is true </u>
Decreasing the temperature decreases the reaction rates because of the decrease in the number of high energy collisions. It will result in a slower reaction.
d) Temperature does not affect the reaction rate. <u>This is not true. </u>
The reaction rate is temperature dependent. The reaction rate increases with higher temperature and decreases with lower temperature.
Explanation:
Note: Molar masses of elements can be found online or in the periodic table.
Moles of Magnesium
= 3.60g / (24.3g/mol) = 0.148mol.
Moles of Chlorine
= 10.65g / (35.45g/mol) = 0.300mol.
Mole ratio of Magnesium to Chlorine
= 0.148mol : 0.300mol = 1 : 2.
Hence we have the empirical formula MgCl2.
Moles of Lithium
= 9.1g / (6.94g/mol) = 1.311mol.
Moles of Oxygen
= 10.4g / (16g/mol) = 0.650mol.
Moles ratio of Lithium to Oxygen
= 1.311mol : 0.650mol = 2 : 1.
Hence we have the empirical formula Li2O.
Answer:
C.) That all matter was composed of earth, fire, water and air
Explanation:
Just took the test
Answer:
and birds can fly without wings es hora de vomer
Question 9. The first one is the smallest. Anything with a negative exponent is going to be less than 1, the .00000241. The exponent tells you the number of zeroes to the right of the decimal point. Farther to right gets smaller and smaller.
Question 10. The last one is true. If the last digit is smaller than 5, drop the digit, and do not change. (If it is a 5 or larger, the digit before it would round up)
