Answer:
8.73
Explanation:
when you are adding or subtracting numbers, the sigfig (significant figure) is based on how many numbers after the decimal. with this info, we can see that 15.67 has 2 sigfigs and 6.943 has 3 sigfigs. when you subtract normally, you would get 8.727, which has 3 sigfigs, so you would round the last 7 up to get 8.73 with 2 sigfigs!
also it is to 2 sigfigs because we know that we go by the least number of sigfigs. hope this helped!
Answer:
They form a covalent bond
A. <span>the layer of rock and mineral fragments that covers nearly all of Earth's land surface</span>
The energy required to break existing chemical bonds in reactants is called the activation energy.
<h3>What is activation energy?</h3>
Activation energy in chemistry is the energy required to initiate a chemical reaction.
Chemical reactions involve the breaking of chemical bonds in substances called reactants to form new substances called products.
The energy required to break the bond in the existing reactants thus elevating these substances to a state of high activation is known as activation energy.
Therefore, it can be said that energy required to break existing chemical bonds in reactants is called the activation energy.
Learn more about activation energy at: brainly.com/question/11334504
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Nitrogen. air consists 78% of nitrogen gas
