Answer:can u anser my question
Explanation: On page 17, author Joey Bartolomeo writes “Caleb participated in the investigation by testifying about what happened during the health seminar at his school.” As it is used in that sentence, what does "testify" mean? *
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C. to persuade someone to join a group
B. to disguise or hide from sight
A. to argue so as to make a person agree
D. to talk and answer questions about something after formally promising to tell the truth
A. is decomposition so HCL = H2 + Cl2
not balanced cause hcl needs 2
2HCL = H2 + Cl2
balanced
b. Br2 + Al-i = AlBr3 + I2 single rep.
not balanced since br need 3 so watch carefully cause many changes needed
3Br2 + Al-i = AlBr3 + I2 not right is unbalanced so make it 2
3Br2 + Al-i = 2AlBr3 + I2 now left Al is unbal. so make 2 there
3Br2 + 2Ali = 2AlBr3 + I2
Balanced
C. Na + S = Na2S synthesis reaction is not bal. left Na needs 2
2Na + S = Na2S balanced.
Pesticides are best described as a substance used for destroying or killing insects and pests harmful to plants and animals.
Empirical formula is calculated as follows
calculate the moles of each element, that is % composition/ molar mass
molar masses ( Si= 28.09g/mol , Cl= 35.5 g/mol, I=126.9 g/mol)
moles of silicon = 7.962/28.09g/mol= 0.283 moles
moles of chlorine = 20.10 / 35.5g/mol = 0.566 moles
moles of iodine= 71.94 / 126.9 g/mol= 0.567 moles
divide each mole with smallest mole (0.283)
that is silicon = 0.283/0.283= 1 mole
chlorine = 0.566/0.283= 2 mole
Iodine= o.567/0.283= 2 moles
empirical formula is therefore= SiCl2I2